Elijah's total earnings for the week if he made x dollars in sales would be: $500 + 0.3x.
What is sale?
A sale is an event or activity in which goods or services are sold at a reduced or discounted price.
What is discount?
A discount is a reduction in the price of an item or service. It is often offered as a promotion or incentive to encourage customers to buy or use a product or service.
According to given information:Total sales commission earned by Elijah for selling $775 worth of clothing:
30% of $775 = 0.3 x $775 = $232.50
Therefore, Elijah's total earnings for the week would be:
$500 (guaranteed salary) + $232.50 (commission) = $732.50
For selling x dollars worth of clothing, the commission earned by Elijah would be:
0.3x
Therefore, Elijah's total earnings for the week if he made x dollars in sales would be:
$500 (guaranteed salary) + 0.3x (commission) = $500 + 0.3x
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mr. allen has a wife and three children. His monthly slary during the year 2007 was $7500. Calculate his annual salary
Mr. Allen's annual salary in the year 2007 was $90,000.
What is the annual salary of mr Allen?Given that, mr. Allen has a wife and three children. His monthly salary during the year 2007 was $7500.
To calculate Mr. Allen's annual salary, we need to multiply his monthly salary by the number of months in a year:
Annual salary = Monthly salary × Number of months in a year
Since Mr. Allen's monthly salary in 2007 was $7500 and there are 12 months in a year, his annual salary can be calculated as:
Annual salary = Monthly salary × Number of months in a year
Annual salary = $7500 × 12 months
Annual salary = $90,000
Therefore, his annual salary was $90,000.
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What is the area of the PURPLE triangle below?
Answer:
Area = 14 in²
Step-by-step explanation:
is a rectangle bisected by the diagonal forming two congruent right triangles, so AD = BC and AB = CD
Area = 1/2 b * h
Area =1/2 7 * 4
Area = 3.5 * 4
Area = 14 in²
So we have 7 in. and 4 in. so we just will mutilply It, So what we do here Is mutilply so we will do 7 x 4 = 28
So we have 28 then we mutilpy all of chocies to see which one Is 28.
A rectangle bisected by the diagonal forming two congruent right triangles, so AD = BC and AB = CD
11 x 2=22 ❌ Not 28
14 x 2 = 28 ✅ Is 28
22 x 2 = 44 ❌ Not 28
28 x 2 = 56 ❌ Not 28
Step 2:A rectangle bisected by the diagonal forming two congruent right triangles, so AD = BC and AB = CD
Area = 1/2 b * h ❌
Area = 3.5 * 4 ❌
Area = 3.5 * 4 ❌
Area = 14 in² ✅
savvas realize topic 5 assesment
Finally, express the solution as an interval of real numbers or as a set of values that make the inequality. x<10.4, x>3.3, x≥32 and x≤-15.
How to solve inequality?To solve an inequality, you need to find the set of values that make the inequality true. The process for solving an inequality depends on the type of inequality and the variables involved. Here are the general steps:
Determine the type of inequality: Is it a greater than (>), less than (<), greater than or equal to (≥), or less than or equal to (≤) inequality?Simplify both sides of the inequality as much as possible using algebraic operations such as addition, subtraction, multiplication, and division. Remember to apply the same operation to both sides of the inequality.If you multiplied or divided both sides of the inequality by a negative number, you need to reverse the direction of the inequality. For example, if you multiplied both sides of x < 3 by -1, you would get -x > -3.If there are variables on both sides of the inequality, move them all to one side of the inequality and simplify.If there are absolute values in the inequality, you may need to split the inequality into two separate cases, one for when the quantity inside the absolute value is positive, and one for when it is negative.Finally, express the solution as an interval of real numbers or as a set of values that make the inequality true. If the inequality is strict (> or <), use an open interval (e.g., (a, b)). If the inequality includes equality (≥ or ≤), use a closed interval (e.g., [a, b]).
by the question.
a. x-3.5>6.9
x>6.9+3.5
x>10.4
b. 6.4>x+3.1
x[tex]\geq 32[/tex]
c. x/4≤8
x≤32
d. 2/3x≤-10
x≤-15
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if x= 60 would they be similar or not? explain ur answer.
Answer: no they wouldn't be similar
Step-by-step explanation: if x=60 if triangle 1 then the third angle would be (180-(58+60)) =180-118=62
if we decide to calculate the third angle in triangle 2 we will have 180-(50+58) = 180-108=72
therefore not all angles in 1 are similar to angles in 2 so the triangles aren't similar
The slope of a line is undefined, and the x-intercept is -7. What is the equation of the line?
Oy=-7
Ox=-7
Oy=-7x
Answer:
"Undefined slope"
Step-by-step explanation:
The line is vertical on the graph.
Every point on the line has the same x-coordinate.
If the line crosses the x-axis where x=-7, then the
x-coordinate of every point on the line is -7, and the
equation of the line is
x = -7 .
I will mark you brainiest!
If AB = 35,BC = 15, and EF = 60, then the value of DE IS
A) 140
B) 180
C) 200
D) 210
AB/BC = DE/EF
35/15 = DE/60
DE = 35*60 / 15
DE = 140
answer
A 140
Find the least common multiple of 44 , 18and 4 ?
A 3,168
B 66
C 396
D 792
E none of these answers are correct
Please help!!
Answer:
C. 396
Step-by-step explanation:
You want the LCM of 4, 18, and 44.
LCMYou can find the least common multiple by considering the unique factors to their highest powers.
4 = 2^2
18 = 2·3^2
44 = 2^2·11
The unique factors are 2, 3, 11, and their highest powers are 2, 2, and 1, respectively. The LCM is ...
2² × 3² × 11 = 396
__
Check
396 = 4·99 = 18·22 = 44·9 . . . . . 99, 22, and 9 have no common factors
(HELP ASAPPP)
Rose plans to have two children but doesn't know if they will be boy-boy, girl-girl, girl-boy, or boy-girl. What is the probability that she will have
boy-girl?
A: 0.5
B: 0.75
C: 0.25
D: 1.00
Answer:
liv
Step-by-step explanation:
Help asap will give brainiest
Use the image to determine the line of reflection.
4
3
2
1
0
?
Ty
5
-6
-7
-8
-9
-10
1
2
B
A
A
3₂
Α',
В'
4
E
5
E
6
с
Reflection across x = 6
D'
Reflection across the x-axis
Reflection across y = -3
C₁
Reflection across the y-axis
Answer: D
Step-by-step explanation: so if we look at the picture, youll notice 2 things right off the bat, firstly, the top shape goes over the y axis, so that wont work, secondly, the shapes are on the same side of the x axis (the positive side) so that wouldnt work, the last thing we now have to look at is making the shapes even, essentially if you were to flip one shape over a certain distance, the mirrored shape needs to be the same distance you flipped the first shape. In this case, if we flip shape 1, over -3, the other shape will be 6 spaces away from the 1st shape, because you need to also move the second shape 3 spaces away from where you flipped the first shape.
side note: reflecting over the x axis or y axis, means the line of reflection is equal to 0 on either the y axis or x axis
To try to make this less confusing, another way to find the reflection is by evenly counting the shapes to the middle, how-ever many squares/spaces it takes for both shapes to reach the center of the two in this case, is how many spaces they are reflected.
The image undergoes a reflection at y=-3, Option D is correct.
What is Graph?Graph is a mathematical representation of a network and it describes the relationship between lines and points.
A translation is a movement of the graph either horizontally parallel to the -axis or vertically parallel to the -axis.
Reflections are congruence transformations that generate a mirror image of an object, without changing its size or shape.
In the given figure the above image is original and it is flipped to form the image which is below the x axis.
In this case, if we flip shape 1, over -3, the other shape will be 6 spaces away from the 1st shape, because you need to also move the second shape 3 spaces away from where you flipped the first shape.
Hence, the image undergoes a reflection over y axis which is at y=-3.
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A rocket is launched from the ground and follows a parabolic path. At the same time, a flare is launched from a height of 14 feet and follows a straight path. The following equations model a relationship between height of the object (y) and flight time (x)
Show your full work
Rocket: y = -x^2 + 8x
Flare: y = -x +14
Identify when the rocket and flare will collide first and their height at this time.
Time:
Height:
The maximum height οf the rοcket is 16 feet.
What is a System οf Equatiοns?A system οf equatiοns in algebra is made up οf twο οr mοre equatiοns that are sοlved tοgether. "A grοup οf equatiοns satisfied by the same set οf variables are called a system οf linear equatiοns. Finding the values οf the variables emplοyed in the system οf equatiοns is the first step tοwards sοlving it.
While maintaining the balance οf the equatiοns οn bοth sides, we cοmpute the values οf the unknοwn variables. Finding a variable whοse value makes the cοnditiοn οf all the given equatiοns true is the primary gοal οf sοlving an equatiοn system.
(x - 2)(x - 5) = 0
Sο x = 2 οr x = 5.
If x = 2, then frοm the equatiοn οf the flare, we have y = -2 + 14 = 12.
If x = 5, then frοm the equatiοn οf the flare, we have y = -5 + 14 = 9.
Sο the twο οbjects intersect at the pοints (2, 12) and (5, 9).
Tο find the maximum height οf the rοcket, we can use the fοrmula fοr the x-cοοrdinate οf the vertex οf a parabοla:
x = -b/2a
In this case, a = -1 and b = 8, sο we have:
x = -8/-2 = 4
Sο the rοcket reaches its maximum height at x = 4. Tο find the maximum height, we can substitute x = 4 intο the equatiοn fοr the rοcket:
[tex]y = -4^2 + 8(4) = 16[/tex]
Sο the maximum height οf the rοcket is 16 feet.
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A car salesman was able to sell a car for 12,500, earning a commission of 5%. How much was his commission.
Answer:
12,500 is 100%, or 1 in decimal terms. We calculate 5% by multiplying 12500 by 0.05.
This gives us a total of £625
Step-by-step explanation:
Brainliest pls
What is the meaning of "finite sequences"?
A finite sequence is a sequence with a finite number of elements, that is, a sequence that has a definite beginning and end.
Describe Sequence?In mathematics, a sequence is a set of numbers, arranged in a particular order. Each number in the sequence is called a term or element of the sequence, and is identified by its position or index in the sequence. For example, the sequence of natural numbers 1, 2, 3, 4, 5, ... can be represented as {a_n}, where a_1 = 1, a_2 = 2, a_3 = 3, and so on.
A sequence can be either finite or infinite. A finite sequence has a fixed number of terms, while an infinite sequence continues indefinitely. A sequence can also be arithmetic, geometric, or neither.
An arithmetic sequence is a sequence in which each term is obtained by adding a constant value, called the common difference, to the previous term. For example, the sequence 2, 5, 8, 11, 14, ... is an arithmetic sequence with a common difference of 3.
In mathematics, a sequence is an ordered list of elements, typically numbers or other mathematical objects, that are written in a particular order. A finite sequence is a sequence with a finite number of elements, that is, a sequence that has a definite beginning and end.
For example, the sequence {1, 2, 3, 4, 5} is a finite sequence of five elements. The first element is 1, the second element is 2, and so on, until the last element, which is 5. The sequence {1, 1/2, 1/4, 1/8, 1/16} is another example of a finite sequence, this time of decreasing terms.
Finite sequences are used in many areas of mathematics, including algebra, calculus, and number theory. They are often studied in their own right, and their properties and patterns can be used to solve problems and prove theorems.
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Soils
there are different types of soil, each with its own set of characteristics. Soil is made of layers, or horizons. You can dig into the ground to see the soil horizons, much like the picture seen here. When you put the horizons together, from top to bottom, you create a soil profile. A soil profile tells a story about the area and the type of life growing there. Most soils have three major horizons, A, B, C, and some have an organic horizon, O.
O -Humus: Mostly organic matter such as decomposing leaves; is thin in some soils, thick in others, or not present at all.
A -Topsoil: Mostly minerals from parent material with organic matter incorporated; good material for plants to live.
B - Subsoil: Rich in minerals that leached upper layers.
C - Parent material: The deposit at Earth’s surface from which the soil developed.
The illustration is a typical soil profile. How would you expect the soil profile to change in a mountainous region?
a
Horizon O would not be present because plants do not grow on mountains.
b
Horizon C would be much deeper because of the bedrock in the mountain itself.
c
Horizon A would be less deep since there would be less topsoil due to erosion.
d
Horizons O, A, and B would be gone because of high winds.
c) Horizon A would be less deep since there would be less topsoil due to erosion.
how to find soil profile?the soil profile in a mountainous region would typically be different from the one shown in the illustration, because the soil formation process is affected by different factors such as climate, vegetation, topography, and parent material.
In a mountainous region, the soil profile is likely to be thinner and shallower than in flat areas, due to the steep slopes and higher erosion rates. The topsoil horizon (A) may also be thinner or absent in some areas due to erosion or limited plant growth, which can make it difficult for organic matter to accumulate. In addition, the subsoil horizon (B) may be more prominent and closer to the surface due to the leaching of minerals from the upper layers, which can result in a more rocky and mineral-rich soil.
Therefore, the correct answer would be:
c) Horizon A would be less deep since there would be less topsoil due to erosion.
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how many solutions does it have?
2y=2x
Y=x
For the system of equations 2y = 2x and y = x, there are infinite number of solutions.
What is an equation?
A mathematical definition of an equation is a claim that two expressions are equal when they are joined by the equals sign ("=").
The system of equations given by 2y = 2x and y = x can be solved by substituting y = x into the first equation -
2y = 2x
Substituting y = x, we get -
2x = 2x
Now, on simplifying, we get -
x = x
The equation x = x is true for all values of x.
Therefore, there are infinitely many solutions to this system of equations.
In geometric terms, the two equations represent two lines in the coordinate plane that intersect at every point on the line y = x.
Therefore, the number of solutions is infinite.
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3
Select the correct answer.
What is the simplified form of 3√7-5√7?
OA. -2√7
OB. 2√7
OC. -√14
OD. 15√7
Answer: A. -2√7
Step-by-step explanation:
3√7 - 5√7
= -2√7
Match each expression to its equivalent expression.
Answer: top two goes together, middle left goes to bottom right, bottom left goes to middle right
Step-by-step explanation:
Substitute x for an easy number like 2 and solve.
x - 2/3 - 1/2x = 1/2x - 2/3
x - 1/2 - 3/4x = 1/4x- 1/2
1/3x - 3/4 - 2/3x = -1/3x - 3/4
please answer need help
Need help pls
geometry
#23
Answer: I think its C
Answer:
Step-by-step explanation:
C is false. [tex]\angle BEC = \angle AED=126[/tex] (vertically opposite).
The rest are correct.
HELP
7th Grade Math Solving Equations
4. a-9=15
5. n-9=13
6. b-8=9
7. X-5=16
8. n-6=17
Answer:
4.
a-9=15
or. a=15+9
or. a=24
5.
n-9=13
or. n=13+9
or. n=22
6.
b-8=9
or. b=9+8
or. b=17
7
x-5=16
or. X=16+5
or X=21
8
n-6=17
or. n= 17+6
or. n=23
Step-by-step explanation:
minus sign changes into plus sign when changing sides
How many solutions does the system of nonlinear equations graphed below
have?
A. Zero
B. Several
C. Infinite
D. One
Hence, the system with nonlinear equations may contain one of these kinds of answers, depending on the particular equations and their graph.
How do nonlinear equations work?Unable to form a straight line is a non-linear equation. With a fluctuating slope value, it resembles a graphed curve.
In general, there can be zero, one, many, or an infinite number of solutions to a system of nonlinear equations. It depends on the particular equations and how those interact with one another.
The problem has zero solutions if there are no values of the parameters that satisfy both equations, which occurs when the equations are inconsistant.
A single solution exists for the system if the equations cross at that point.
The system has multiple solutions if the equations cross more than once.
The system has an infinite number of solutions if the equations all describe the same curve.
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a jewelry store recently sold 52 pices of jewelry and 22 of them were braclets what is the experimental probability that the next piece of jewerly sold will be a bracelet
The experimental probability that the next piece of jewelry sold will be a bracelet is of 11/26.
How to calculate a probability?A probability is calculated as the division of the desired number of outcomes by the total number of outcomes in the context of a problem/experiment.
For the experimental probability that the next piece of jewelry sold will be a bracelet, the outcomes are given as follows:
Desired outcomes: 22 pieces sold that were a bracelet.Total outcomes: 52 pieces sold.Hence the experimental probability that the next piece of jewelry sold will be a bracelet is obtained as follows:
p = 22/52
p = 11/26.
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The value of X is
A) 3
B) 5
C) 9
D) 12
Therefore, the value of x is 9.
What is triangle?A triangle is a closed two-dimensional geometric shape that is formed by connecting three non-collinear points with three-line segments. The three line segments that connect the three points are called sides of the triangle, and the points themselves are called vertices. The angle formed between any two adjacent sides of a triangle is called an interior angle of the triangle. The sum of the interior angles of a triangle is always 180 degrees.
There are many different types of triangles, including equilateral triangles, isosceles triangles, scalene triangles, acute triangles, obtuse triangles, and right triangles. An equilateral triangle is a triangle in which all three sides are equal, an isosceles triangle is a triangle in which two of the sides are equal, and a scalene triangle is a triangle in which none of the sides are equal. An acute triangle is a triangle in which all three interior angles are less than 90 degrees, an obtuse triangle is a triangle in which one of the interior angles is greater than 90 degrees, and a right triangle is a triangle in which one of the interior angles is exactly 90 degrees.
Given by the question.
According to Thel's theorems
[tex]\frac{5}{3} =\frac{15}{x}[/tex]
5x=45
x=9
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Simplify the expression below.
5^2 + 9^2
To simplify the expression 5^2 + 9^2, we can evaluate the squares of 5 and 9 and then add the results:
5^2 = 5 x 5 = 25
9^2 = 9 x 9 = 81
So, 5^2 + 9^2 = 25 + 81 = 106
Therefore, the simplified form of the expression 5^2 + 9^2 is 106.
The amount of time to complete a physical activity in a PE class is normally distributed with a mean of 34.7
seconds and a standard deviation of 7.6 seconds. Round answers to 4 decimal places.
a) What is the probability that a randomly chosen student completes the activity in less than 30.1 seconds?
b) What is the probability that a randomly chosen student completes the activity in more than 38.1
seconds?
c) What proportion of students take between 30.9 and 38.5 seconds to complete the activity?
d) 90% of all students finish the activity in less than
seconds.
Answer:
a) To find the probability that a randomly chosen student completes the activity in less than 30.1 seconds, we need to standardize the value using the formula z = (x - mu) / sigma, where x is the time taken, mu is the mean, sigma is the standard deviation, and z is the standard normal variable.
z = (30.1 - 34.7) / 7.6 = -0.6053
Using a standard normal distribution table or calculator, we find that the probability of a standard normal variable being less than -0.6053 is 0.2739.
Therefore, the probability that a randomly chosen student completes the activity in less than 30.1 seconds is 0.2739.
b) To find the probability that a randomly chosen student completes the activity in more than 38.1 seconds, we need to standardize the value using the same formula.
z = (38.1 - 34.7) / 7.6 = 0.4474
Using a standard normal distribution table or calculator, we find that the probability of a standard normal variable being greater than 0.4474 is 0.3274.
Therefore, the probability that a randomly chosen student completes the activity in more than 38.1 seconds is 0.3274.
c) To find the proportion of students taking between 30.9 and 38.5 seconds, we need to standardize both values and then find the area between them in the standard normal distribution.
z1 = (30.9 - 34.7) / 7.6 = -0.5
z2 = (38.5 - 34.7) / 7.6 = 0.5
Using a standard normal distribution table or calculator, we find that the probability of a standard normal variable being between -0.5 and 0.5 is 0.3830.
Therefore, the proportion of students taking between 30.9 and 38.5 seconds to complete the activity is 0.3830.
d) To find the time taken by 90% of all students to finish the activity, we need to find the z-value corresponding to the 90th percentile of the standard normal distribution using a standard normal distribution table or calculator.
The z-value corresponding to the 90th percentile is approximately 1.28.
Now, we can use the formula z = (x - mu) / sigma to find the corresponding time value.
1.28 = (x - 34.7) / 7.6
x - 34.7 = 1.28 * 7.6
x - 34.7 = 9.728
x = 44.428
Therefore, 90% of all students finish the activity in less than 44.428 seconds.
A baseball rolls off a 0.7m high desk and strikes the floor 0.25m away from the base of the desk. How long will it take for the ball to hit the ground?
Answer: 2.45 m/s.
acceleration due to gravity 9.8 m/s
Answer ASAP ASAP its in photo
Answer:x=11.42
Step-by-step explanation:
[tex]\frac{35}{20} =\frac{20}{x}[/tex]
[tex]35x=400[/tex]
[tex]X=11.42[/tex]
Hodgman Honest is evaluating a new project for her firm, Basket Wonders (BW). She has determined that the after-tax cash flows for the project will be $10,000; $12,000; $15,000; $10,000; and $7,000, respectively, for each of the Years I through 5. The initial cash outlay will be $40.000. For this project, assume that it is independent of any other potential projects that Basket Wonders may undertake. The management of Basket Wonders has set a maximum PBP of 3.5 years for projects of this type. Required: Evaluate this project using payback period technique and advise the management accordingly.
Answer:
To calculate the payback period (PBP) for this project, we need to determine how long it will take for the initial cash outlay of $40,000 to be recovered from the after-tax cash flows.
Year 1 cash flow = $10,000
Year 2 cash flow = $12,000
Year 3 cash flow = $15,000
Year 4 cash flow = $10,000
Year 5 cash flow = $7,000
Total cash inflows for year 1 and year 2 = $10,000 + $12,000 = $22,000
Total cash inflows for year 3 = $15,000
Total cash inflows for year 4 = $10,000
Total cash inflows for year 5 = $7,000
Cumulative cash inflows for year 1 and year 2 = $22,000
Cumulative cash inflows for year 3 = $37,000
Cumulative cash inflows for year 4 = $47,000
Cumulative cash inflows for year 5 = $54,000
It can be seen that the cumulative cash inflows reach the initial cash outlay of $40,000 after year 2, and therefore the payback period for this project is 2 years. Since the payback period is less than the maximum PBP of 3.5 years set by management, this project can be considered acceptable.
So, Hodgman Honest should recommend that Basket Wonders should accept this project as it has a payback period of only 2 years, which is less than the maximum PBP of 3.5 years set by management.
Which of the following completes the equation 30 100 + 9 10 ?
The expression that completes the equation the result of 30/100 + 9/10 is 1.2.
What fundamental equation format is used?The typical form for linear equations with two variables is Ax+By=C. For instance, the linear equation 2x+3y=5 is in standard form. When attempting to solve problems containing two linear equations, this form is also quite helpful.
We must multiply the values of 30 and 100, then add the resulting product to the resulting product of the values of 9 and 10 in order to complete the equation 30 100 + 9 10.
The result of multiplying 30 by 100 is:
30 x 100 = 3000
The result of adding 9 and 10 is:
9 x 10 = 90
Thus, we must combine these two items to finish the equation:
3000 + 90 = 3090
30100 + 910 = 3090, which is the expression that completes the equation.
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the complete question is:
complete the equation
[tex]\frac{30}{100}+\frac{9}{10}[/tex]
Answer:
The answer is 39/100
Step-by-step explanation: Nothing more.
In simplest radical form, what are the solutions to the quadratic equation 0 = –3^2 – 4x + 4
Answer: x = -2, [tex]\frac{2 }{3}[/tex]
Step-by-step explanation:
Given:
0 = –3x² – 4x + 4
The quadratic formula:
[tex]\displaystyle x=\frac{-b\pm\sqrt{b^2-4ac} }{2a}[/tex]
Substitute known values:
* a = -3, b = -4, c = 4
[tex]\displaystyle x=\frac{-(-4)\pm\sqrt{(-4)^2-4(-3)(4)} }{2(-3)}[/tex]
Simplify with multiplication:
[tex]\displaystyle x=\frac{4\pm\sqrt{16+48} }{-6}[/tex]
Simplify:
[tex]\displaystyle x=\frac{4\pm\sqrt{64} }{-6}[/tex]
[tex]\displaystyle x=\frac{4+8 }{-6}[/tex], [tex]\displaystyle x=\frac{4-8 }{-6}[/tex]
[tex]\displaystyle x=\frac{12 }{-6}[/tex], [tex]\displaystyle x=\frac{-4 }{-6}[/tex]
A student wants to investigate the chemical changes that a piece of wood undergoes when it is burned. He believes wood that burns for 15 minutes will weigh less than unburned wood. Design a laboratory experiment that would allow the student to test his predictions, using appropriate equipment and technology. Be sure to consider safety requirements in your answer.
Answer:
Experimental Procedure:
Materials:
Piece of wood
Electronic balance
Bunsen burner
Heat-resistant mat
Stopwatch or timer
Safety goggles
Lab coat
Safety Precautions:
Wear safety goggles and a lab coat to protect your eyes and clothing from any sparks or flames.
Place the heat-resistant mat under the Bunsen burner to prevent any accidental fires.
Use the Bunsen burner only under adult supervision.
Be cautious when handling hot objects, and allow them to cool before touching.
Procedure:
Measure the initial mass of the piece of wood using an electronic balance, and record it in a table.
Light the Bunsen burner, and place the piece of wood over the flame using tongs. Ensure that the wood is fully engulfed in the flame.
Use a stopwatch or timer to time how long the wood burns for (in this case, 15 minutes).
After 15 minutes, turn off the Bunsen burner and remove the piece of wood from the flame using tongs.
Allow the wood to cool, and then measure its final mass using the electronic balance, and record it in the table.
Calculate the difference between the initial and final mass of the wood, and record it in the table.
Repeat steps 1-6 three times to obtain three sets of data.
Calculate the average mass of the burned wood and compare it to the initial mass of the unburned wood to determine if the student's prediction was correct.
Conclusion:
If the average mass of the burned wood is less than the initial mass of the unburned wood, the student's prediction was correct, and he can conclude that the wood underwent a chemical change when it was burned. If the average mass is greater than or equal to the initial mass, the prediction was incorrect, and the student may need to revise his hypothesis or experimental design.