Answers
Answer:
D
Step-by-step explanation:
We want to find the values of x such that:
[tex]\displaystyle -x^2 + 7x + 5 = 0[/tex]
We can use the quadratic formula. Recall that:
[tex]\displaystyle x = \frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
In this case, a = -1, b = 7, and c = 5. Substitute and evaluate:
[tex]\displaystyle \begin{aligned} x & = \frac{-(7)\pm\sqrt{(7)^2-4(-1)(5)}}{2(-1)}\\ \\ & = \frac{-7\pm\sqrt{49+20}}{-2} \\ \\ & = \frac{-7\pm\sqrt{69}}{-2}\end{aligned}[/tex]
In conclusion, the answer is D.
Related Questions
8) Use the formula for the cardinal number of union of two sets
n(AUB) = n(A) + n(B) – n(An B)
n
to solve the problem.
Set A contains 10 elements, set B contains 5 elements and 3 elements are common
to sets A and B. How many elements in the union of these two sets?
18
09
12
15
Answers
Answer:
12
Step-by-step explanation:
n(AUB) = n((A) + n(B) – n(AnB)
Step 1:
Identify the values for each function of the formula. n(A) = 10, n(B) = 5, n(AnB) = 3
Step 2:
Replace each function with its values
n(AUB) = n(A) + n(B) – n(AnB)
n(AUB) = 10 + 5 – 3
Step 3:
Carry on the simple arithmetic
n(AUB) = 10 + 5 – 3 (follow the BODMAS method)
= 15–3
= 12
Therefore, the n(AUB) is 12
A scale drawing of a rectangular playground has a length of 20 inches and a width of 10 inches as shown.The scale is 1 inch = 15 feet.
Write a scale that relates the area of the drawing to the area of the actual playground. Show or explain your work and write your answer in the space provided.
Answers
Answer:
4:9
Step-by-step explanation:
Find the area in inch first:
20 inch × 10 inch = 200 inch
Area in feet:
(20×15) + (10×15) = 450 inch
Area of the drawing : Area of the actual playground
200:450
Simplify it by dividing by 5
Last answer =4:9
The two solids are similar, and the ratio between the lengths of their edges is
2:9. What is the ratio of their surface areas?
36 2
A. 64:729
B. 4:81
C. 4:18
D. 8:36
Answers
Surface area is the sum of the area of faces of a figure. The ratio of their surface area is 2268 : 112
How to calculate the surface area of a prism?A prism is a solid shape with 6 faces
The formula for calculating the total surface area is expressed as:
TSA = 2(lw+wh+lh)
l is the lengthw is the widthh is the heightFor the Red prism
Ar = 2(162 +324 + 648)
Ar = 2268 square units
For the blue prism
Ab = 2(8 + 16 + 32)
Ab = 112 square units
Take the ratio of the surface area
Ratio = 2268 : 112
Hence the ratio of their surface area is 2268 : 112
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Surface area is the sum of the area of faces of a figure. The ratio of their surface area is 4:81.
How to calculate the surface area of a prism?
A prism is a solid shape with 6 faces
The formula for calculating the total surface area is expressed as:
TSA = 2(LW+WH+LH)
L is the lengthW is the widthH is the heightFor the Red prism
Ar = 2(648 + 162 + 324)Ar = 1,782 square unitsFor the blue prism
Ab = 2(32 + 8 + 16)Ab = 88 square unitsTake the ratio of the surface area
Ratio = 4:81
Hence the ratio of their surface area is 4:81
Learn more on the surface area here: brainly.com/question/76387
I need asap please
What square root best approximates the point on the graph?
A) 5 to the square root
B) 15 to the square root
C)28 to the square root
D) 53 to the square root
Answers
Answer:
[tex]\sqrt{28}[/tex]
Step-by-step explanation:
the point lies between 5 and 6 , that is between
[tex]\sqrt{25}[/tex] and [tex]\sqrt{36}[/tex]
therefore the poi nt approximates to the [tex]\sqrt{28}[/tex]
Suppose that in your city % of the voters are registered as Democrats, % as Republicans, and % as members of other parties. Voters not aligned with any official party are termed "Independent." You are conducting a poll by calling registered voters at random. In your first three calls, what is the probability that you talk to
Answers
Answer:
it will depend on what state you are in
Step-by-step explanation:
depending on what state you are in will depend on the voting polls. and it would most likely be democratic
I WILL GIVE 20 POINTS TO THOSE WHO ANSWER THIS QUESTION RIGHT NOOOO SCAMS AND EXPLAIN WHY THAT IS THE ANSWER
Answers
Answer:
45 degrees
right angle =90 degrees
remaining :90
angles are equal
so 45 each
help me please…………….
Answers
Answer:
The answer is e. (x - 10 * y^2 * z) (x + 10 *y^2 *z)
Step-by-step explanation:
To explain it test all the options by distributing them.
Using an online website that I plugged into the calculator to factory gets answer e.
Consider the given probability histogram of a binomial
random variable.
What are the center and shape of the distribution?
0.4
A. Center: 2
Shape: symmetric
B. Center: 2.5
Shape: symmetric
C. Center: 2.5
Shape: slightly skewed
D. Center: 3
Shape: uniform
Answers
The center and shape of the distribution are 2.5 and symmetric. Then the correct option is B.
How to find that a given condition can be modeled by binomial distribution?Binomial distributions consist of n independent Bernoulli trials.
Bernoulli trials are those trials that end up randomly either on success (with probability p) or on failures( with probability 1- p = q (say))
Suppose we have random variable X pertaining to a binomial distribution with parameters n and p, then it is written as
[tex]X \sim B(n,p)[/tex]
The probability that out of n trials, there'd be x successes is given by
[tex]\rm P(X =x) = \: ^nC_xp^x(1-p)^{n-x}[/tex]
Then the center and shape of the distribution will be 2.5.
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Answer:
Center : 2.5 Shape: Symmetric
Step-by-step explanation:
Trust Fam
what is the distance between (7, -7) and (9,-9)
Answers
Answer: 2,-2
Step-by-step explanation: 9-7 is 2 and -9 minus -7 is minus 2.
What is 6x^3 - 3x^2 + 7x - 4
when x = 5?
Answers
706
Step-by-step explanation:
Substitute x=5 in the equation:
6(5)^3 - 3(5)^2 + 7(5) - 4
= 6(125) - 3(25) + 35 - 4
=750 - 75 + 35 - 4
=706
So the answer is 706
Step-by-step explanation:
[tex] = {6x}^{3} - {3x}^{2} + 7x - 4[/tex]
[tex] = 6 \times 125 - 3 \times 25 + 7 \times 5 - 4[/tex]
[tex] = 750 - 75 + 35 - 4[/tex]
[tex] = 750 + 35 - 75 - 4 [/tex]
[tex] = 706..[/tex]
Which answer is an example of systematic sampling?
asking every fifth person their age
asking your neighbors if they approve of the mayor
submitting an online survey
counting everyone who attends a game
Answers
Answer:
Asking every 5th person their age
Step-by-step explanation:
I just did the quiz
Kim is earning money for a trip. She has saved $60 and she earns $10 per hour babysitting. The total amount of money earned
(y) after (x) number of hours worked is given by the equation y = 10x + 60.
How many hours will she need to work in order to earn $300 for her trip?
Answers
Answer:
x=24
Step-by-step explanation:
you need 300.
10x + 60?
10 x 3 = 300
300 - 60 = 240
300 = (10 x 24) + 60
Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar.
Find the area of the rectangle.
8
2
square units
Answers
16 square units
Simplify
5x²-x+ 9 =
X=3
Answers
Answer:
51
Step-by-step explanation:
5x^2 - x + 9
5(3^2) - 3 + 9
5(9) + 6
45 + 6
= 51
The rabbit population in a certain area is 500% of last year's population. There are about 300 rabbits this year. How many were there last year?
Answers
Answer: 1500
Hope this helps! :)
Please mark brainliest.
37. Watering a lawn requires 623 gallons of water for
every 1000 sq. ft. What is the rate of gallons per square
foot?
Answers
The rate of gallons per square foot is 0.624 gallons per square foot.
What is a rate?A rate demonstrates how many times one number can fit into another number. Ratios contrast two numbers by ordinarily dividing them. A/B will be the formula if one is comparing one data point (A) to another data point (B). This indicates that you're dividing information A by B.
In this scenario, watering a lawn requires 623 gallons of water for every 1000 sq. ft.
The rate of gallons per square foot will be:
= Number of gallons / Square foot
= 623 / 1000
= 0.623
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A
Angle ABC Is a right angle.
The measure of angle
DBC is 55°.
The measure of angle ABD Is x
55°
What is the value of x?
B
Answers
Answer:
25
Step-by-step explanation:
ABC is a right angle so ABD and DBC are complementary angles and their sum is equal to 90:
x + 55 = 90 subtract 55 from both sides
x = 25
Otis measured the heights of several sunflowers. He found that their heights were 1, 4, 6, 9, and 10 feet. Otis found that the mean was 6 feet and the range was 9 feet. Which numbers describe the center and spread of this data set?
Answers
Answer: 6 feet describes the center, and 9 feet describes the spread
Step-by-step explanation:
The center of a data set is mostly considered as the median or the mean
Here mean is 6 (given). And median is also 6. As 6 is exactly at the middle of the data set. (When arranged in ascending order)
Now, one of the way of calculating the spread is calculating the range, here it's given that the range is 9.
Therefore, 6 feet describes the center, and 9 feet describes the spread is correct.
Mark earned $1340 for a 40-hour week. Use the formula P = RH where (P is the pay,
R is the rate per hour, and H is the number of hours worked) to find his hourly rate.
Answers
1) Find the circumference and Area
2) Find the Perimeter and Area
Thank you so much!
Answers
Answer:
See below.
Step-by-step explanation:
1) We know that the circumference of a circle can be found using the formula [tex]c=\pi d[/tex], so for this circle the circumference will be [tex]c=3.14 \times 40=125.6 \text{ yards}[/tex]. The formula for the area of a circle is [tex]A=\frac{1}{4}\pi d^2[/tex], so the area of this circle will be [tex]A=\frac{1}{4} \times 3.14 \times 40^2=1256 \text{ yards}[/tex].
2) First we'll work out the length of the curved side of the shape. That's [tex]\frac{1}{2}\times\pi d =\frac{1}{2} \times 3.14 \times 12=18.84 \text{ mm}[/tex]. Then, we'll add the length of the other two straight sides to get [tex]10.82 \times 2 + 18.84=40.48 \text{ mm}[/tex]. Next: the area of the semi-circle is [tex]\frac{1}{2} \times \frac{1}{4} \pi d^2 = \frac{1}{8} \times 3.14 \times 144 = 56.52 \text{ mm}[/tex]. Adding this to the areas of the two triangles: [tex]56.52+2 \times \frac{1}{2}bh=56.52+(\sqrt{10.82^2-9^2)}\times9 \approx 110.57 \text{ to 2 d.p.}[/tex]
At a company, a copy machine prints 175 pages in 5 minutes. If the number of pages printed is proportional to the time, what is the unit rate?
Answers
Answer:
35 pages per minute is the unit rate
Step-by-step explanation:
Divide 175 by 5 to find the unit rate
The sum of three numbers is 145. The third number is 4 times the second. The second number is 5 more than the first. What are the numbers?
Answers
Answer:
i think they are 23, 50, and 64!
Step-by-step explanation:
what is an equation of the line that is perpendicular to line y= -1/2x -2 and passes through the point (0,-4)?
Answers
Answer:
[tex]y = 2x -4[/tex]
Step-by-step explanation:
[tex]y = -\frac{1}{2}x - 2\ \ \ \ \ \ (0, -4)[/tex]
To find the perpendicular equation of a line,
You need the product of their gradients to be -1
[tex]-\frac{1}{2} \times ? = -1[/tex]
Divide both sides by [tex]-\frac{1}{2}[/tex]
? = 2
The gradient of the perpendicular line is 2
Straight line formula is in the form [tex]y = mx + c[/tex]
[tex]y = 2x + c[/tex]
We're nearly there, we just need to find out c.
Luckily, we're given a point [tex](0, -4)[/tex]
[tex](x, y) = (0, -4)[/tex]
[tex]y = 2x + c[/tex]
[tex]-4 = 2(0) + c\\-4 = 0 + c\\c = -4[/tex]
We then end up with...
[tex]y = 2x -4[/tex]
Shanelle used the following steps to arrive at the wrong answer for the simplification problem shown below.
What mistake did Shanelle make to get the problem wrong?
ty
y
Given: 2,5
XyX
10
Step 1: 3,4
xºy
Step 2: = x 'yº
Step 3: = x(1)
Step 4: = x
A. Shanelle misapplied the multiplication property of exponents to x in Step 1.
B. Shanelle misapplied the multiplication property of exponents to y in Step 1.
C. Shanelle misapplied the division property of exponents to x in Step 2.
D. Shanelle misapplied the division property of exponents to y in Step 2.
Answers
Sal the sloth takes one hour to travel 7 1/2 feet. If he continues to travel at the same rate, how long will it take him to travel 30 feet?
Answers
Answer:
4 hours
Step-by-step explanation:
Since we know he travels at a rate of 1:7.5 all we have to do is divide 7.5 by 30. Do you use proportions? You can set this up as a proportion and the find answer easily.
1[tex]\frac{1}{7.5} =\frac{x}{30}[/tex]
Now we cross product.
7.5 multipled by x =7.5x
1x30=30
so now we have
7.5x=30
Now we have to divide 7.5 on both sides which gives us
x=4
what is 2.5 in a fraction?
Answers
Answer: 5/2
To convert 2.5 into a fraction, firstly we will write the number in x/y form, where x and y are positive integers. So, 2.5 can be written as 2.5/1. For the removal of the decimal, we multiply and divide by 10. And we get, 2.5/1 x 10/10 = 25/10 = 5/2.
Lillie has read 45 books and read 10 books every year. Dean has read 23 books and reads 12 books every year. How many years will Dean take to read as many books as Lillie?
Answers
Answer:
11 years
Step-by-step explanation:
x = years to equal
45 + 10x = 23 + 12x
22 = 2x
x = 11 years
It will take 11 years for Dean to read as many books as Lillie.
What is an Equation?An equation is the statement of two expressions located on two sides connected with an equal to sign. The two sides of an equation is usually called as left hand side and right hand side.
Given that,
Number of books read by Lillie every year = 10 books
Total number of books already read = 45 books
The number of books, n, read by Lillie in t years,
n = 45 + 10t
Number of books read by Dean every year = 12 books
Total number of books already read = 23 books
The number of books, n, read by Lillie in t years,
n = 23 + 12t
Dean read as many books as Lillie, when,
23 + 12t = 45 + 10t
12t - 10t = 45 - 23
2t = 22
t = 11
Hence the number of books read by both will be same in 11 years.
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PLEASE HELP ME WITH THIS!!
Answers
PLS ANSWER THIS QUESTION FAST
EXPLANATION IS NOT NEEDED PLS MAKE SURE ITS CORRECT
I WILL MARK BRAINLIEST
Answers
Answer:
C. 16π
Step-by-step explanation:
You want to know the area of a circle whose radius is twice the edge of a cube that has a surface area of 24 square units.
AreaThe relevant area formulas are ...
As = 6s² . . . . . . area of cube with edge s
Ac = πr² . . . . . . area of circle with radius r
ApplicationHere, we have r = 2s, so the area of the circle is ...
Ac = π(2s)² = 4πs²
And we have the area of the square as 24, so the value of s² is ...
As = 24 = 6s²
24/6 = 4 = s²
Using this in the circle area expression, we have the area of the circle as ...
Ac = 4π(4) = 16π . . . . . square units
The area of the circle is 16π square units.
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4) Reflection: why is it important to understand radius and circumference to solve problems in the real world?
Answers
Look at the below example you may understand better
Suppose you are playing soccer or footballYou want to make a perfect ball which can be played easily by people irrespective of their age.So if you know about radius and circumference you can find that .