Answer:
[tex] - 2z - xy = x + 7 \\ x + xy = - 2z - 7 \\ x(1 + y) = - 2z - 7 \\ \\ x = \frac{ - 2z - 7}{1 + y} [/tex]
I hope I helped you^_^
Which expression is equivalent to –9+(-9)
O 9+ (-9)
-9 - 9
Submit Answer
O-9- (-9)
O9- (-9)
Guided Practice
The number of bacteria in a lab sample triples every hour. If you start with 2 bacteria in the sample, write an equation that represents the number of bacteria, y, in the sample after x hours.
A.
y=3 · 2xy equals 3 times 2 superscript x baseline
B.
y=2 · 3xy equals 2 times 3 superscript x baseline
C.
y=2 · x3y equals 2 times x cubed
Answer:
B.
y=2 · 3xy equals 2 times 3 superscript x baseline
Step-by-step explanation:
The bacteria culture starts with 500 bacteria and doubles size every half hour.= 2 hours
32,000
Thus, after three hours, the population of bacteria is 32,000.= 3 hours
A bacteria culture starts with 500 bacteria and doubles in size every half hour.1
(a) How many bacteria are there after 3 hours?
We are told “. . . doubles in size every half hour.” Let’s make a table of the time and population:
t 0 0.5 1.0 1.5 2.0 2.5 3.0
bacteria 500 1000 2000 4000 8000 16000 32000
Thus, after three hours, the population of bacteria is 32,000.
(b) How many bacteria are there after t hours?
In t hours, there are 2t doubling periods. (For example, after 4 hours, the population has doubled 8
times.) The initial value is 500, so the population P at time t is given by
P(t) = 500 · 2
2t
This is an acceptable response, but in calculus and all advanced mathematics and science, we will
almost always want to use the natural exponential base, e. Let’s redo the problem using the natural
exponential growth function
P(t) = P0e
rt
We are given that the initial population is 500 bacteria. So P0 = 500 and we have
P(t) = 500ert
We know that after 1 hour, there are 2000 bacteria. (We could’ve used any other pair from our table
that we wish.) Substituting into our function, we get
P(t) = 500ert
2000 = 500er·1
2000 = 500er
1
500
· 2000 =
1
500
· 500er
4 = er
and now we use the natural logarithm to solve for r
ln (4) = ln (er
)
ln (4) = r · ln (e)
ln (4) = r
1.3863 ≈ r
Thus the function P(t) = 500e1.3863t gives the number of bacteria after t hours.
(c) How many bacteria are there after 40 minutes?
The input t to our function is given in hours, so we must convert 40 minutes into hours. So (40 min)
1 hr
60 min
=
2
3
hr.
P(t) = 500e1.3863t
P
2
3
= 500e1.3863·(2/3)
P
2
3
≈ 1259.9258
Thus, after 40 minutes (2/3 of an hour), there are about 1260 bacteria.
(d) Graph the population function and estimate the time for the population to reach 100,000.
50000
100000
1 2 3 4 5
b
(3.8219, 100,000)
t
P
Using the calc:intersect on the TI-84, we get the point (3.8219, 100000), thus the population will
reach 100,000 in about 3.82 yrs
What 2 divided by 188
Answer:
1/94
Step-by-step explanation:
2/188 = 1/94
Answer:
0.01063829787.
Step-by-step explanation:
Caculator.
What is 5 x 0.1 + 4 x 0.01 + 8 x 0.001 written in standard form?
Answer:
0.548
Step-by-step explanation:
5 x 0.1 = 0.5
4 x 0.01 = 0.04
8 x0.0001 = 0.008
Now add them all together to get 0.548 in standard form.
I hope this helps! :)
Answer:
5 × 0.1 is 0.5
4 × 0.001 is 0.04
8 × 0.0001 is 0.008
so add all number is
0.548
Help me plessss!!
Brainliest to the best answer
If you can with procedimento that i understand how to do that
Answer:
[tex] \frac{r}{2} + ( \frac{7}{8} - s) \\ r = 1 \\ s = \frac{1}{2} \\ then \\ \frac{1}{2} + ( \frac{7}{8} - \frac{1}{2} ) \\ = \frac{1}{2} + \frac{3}{8} \\ = \frac{7}{8} \\ thank \: you[/tex]
Tavon has a gift card for $110 that loses $2.50 for each 30-day period it is not used. He has another gift card for $90 that loses $2 for each 30-day period it is not used.
a. Write and solve an equation for the number of 30-day periods until the value of the gift cards will be equal.
b. What will the value of each card be when they have equal value?
30 day period
The first equation is 50 - 2x (because you start with $50 and subtract 2 for each 30 day period)
The second equation is 40-1.5x
Set them equal to each other: 50 - 2x = 40 - 1.5x
Solve for x:
50 - 2x = 40 - 1.5
+2x +2x
50 = 40 + 0.5 x
-40 -40
-------------------
10 = 0.5 x
20 = x
So there will be 20 30-day periods until the cards will be equal in value.
Check: After 20 periods, 50 - 2(20) = $10 left
40 - 1.5(20) = also $10 left
The equations are y = 110 - 2.5x and y = 90 - 2x. Then the value of each card, when they have equal value, will be $10.
What is a linear equation?A relationship between two or more parameters that, when shown on a graph, produces a linear model. The degree of the variable will be one.
The linear equation is given as,
y = mx + c
Where m is the slope of the line and c is the y-intercept of the line.
Let x be the number of days and y be the value of the card.
Tavon has a gift card for $110 that loses $2.50 for each 30-day period it is not used. He has another gift card for $90 that loses $2 for each 30-day period it is not used. Then the equations will be
y = 110 - 2.5x ...1
y = 90 - 2x ...2
From equations 1 and 2, we have
110 - 2.5x = 90 - 2x
20 = 0.5x
x = 40
And the value of y will be
y = 110 - 2.5(40)
y = 110 - 100
y = $10
The equations are y = 110 - 2.5x and y = 90 - 2x. Then the value of each card, when they have equal value, will be $10.
More about the linear equation link is given below.
https://brainly.com/question/11897796
#SPJ2
How many solutions does the following equation have? 7 x - 5(2x - 4) - 8 = 15 - (3 - x) - 4x
a. no solution
b. exactly one solution
c. at least two solutions
d. infinitely many solutions
Answer:
no soultion
Step-by-step explanation:
did on paper
Answer:
exactly one solution
Step-by-step explanation:
got it right on khan lol
Which is the equation of the line that passes through (6, 2) and is perpendicular to a line with slope -1/3?
Answer:
(c) y = 3x - 16 or y - 2 = 3(x - 6)
Step-by-step explanation:
To be perpendicular, the slope must be the negative inverse of the other line,
so we know the slope must be -(-3/1) = 3
then the general point-slope form is
y = mx + b (m = slope and b = y-intercept) so
y = 3x + b (then use the point given (6,2) to find m)
2 = 3(6) + b
2 = 18 + b
2 - 18 = b
-16 = b
then
y = mx + b
y = 3x - 16
The same seven pieces shown on the top were used to make two different figures as shown (the prices do not overlap anywhere) which if the following will definitely be same for these two figures
Jessica is selling books during the summer to earn money for college. She
earns a commission on each sale but has to pay for her own expenses.
After a month of driving from neighborhood to neighborhood and walking
door-to-door, she figures out that her weekly earnings are approximately a
linear function of the number of doors she knocks on.
She writes the equation of the function like this: E(x) = 10x - 30, where x is the
number of doors she knocks on during the week and E(x) is her earnings for
the week in dollars.
Which of the following are reasonable interpretations of the y-intercept of
Jessica's function?
Check all that apply:
A.) If she does not knock on any doors at all during the week, she will lose $30
B.) She can earn $10 per week even if she does not knock on any doors
C.) She will lose $10 per week if she does not knock on any doors
D.) Her expenses are $30 per week
Answer:
She can earn $10 per week even if she does not knock on any doors
What is the distance
what
between the points
(28,-12) and (28, 6)?
Answer:
[tex]distance = \sqrt{ {(x2 - x1)}^{2} + {(y2 - y1)}^{2} } \\ \sqrt{ {28 - 28)}^{2} + {(6 - - 12)}^{2} } \\ \sqrt{ {0}^{2} + {18}^{2} } \\ = \sqrt{ {18}^{2} } = 18unit \\ thank \: you[/tex]
The expression 36 divided 6 • 2+1 is equal to
A.13
B.4
C.2
D.18
15 points for the question
find the distance travelled in metres at a speed of 55km/h for 2 hours
if x = 6, y = 8, and z = 3.
Find the area to the nearest square foot of the shaded region below, consisting of a square with a circle cut
out of it. Use 3.14 as an approximation for .
10 ft
O 54 square feet
O 79 square feet
o 22 square feet
o 214 square feet
what are the next two numbers in the sequence? 1,3,8,16,
and the sequence 1,26,24,120
Answer:
256, 254
Step-by-step explanation:
Need help fast, with steps
Answer:
D
Step-by-step explanation:
Given the input - 1 [tex]\frac{1}{2}[/tex] = - [tex]\frac{3}{2}[/tex] , then
(- [tex]\frac{3}{2}[/tex] )² = [tex]\frac{9}{4}[/tex] , then subtract 2
[tex]\frac{9}{4}[/tex] - 2 = [tex]\frac{9}{4}[/tex] - [tex]\frac{8}{4}[/tex] = [tex]\frac{1}{4}[/tex]
Then reciprocal which is 1 over the previous value
reciprocal = [tex]\frac{1}{\frac{1}{4} }[/tex] = 4 ← output → D
NEED HELP ILL MARK BRAINLIEST
Find the distance between the two numbers on a number line. Write your answer as a mixed number.
-7, -3 2/3
Answer:
3 1/3
Step-by-step explanation:
A mobile device that normally sells for $99.90 is
marked down 10%. What's the discount price?
$99.00
$89.99
$89.91
$89.90
Answer:
89.90 is the answerrrrrrrrrrr
Answer:
89.91
Step-by-step explanation:
You can do this with a calculator 99.90-10%
OXYZ is a pyramid whose base is a right-angled triangle where XY = 7 m and YZ = 4 m. Given that the height of the pyramid is 5 m, find its volume. please answer
Given:
In the triangular base of the pyramid,
Base = 4m
Height = 7m
Area of base = 1/2 x Base x Height
=> 1/2 x 4 x 7 = 14 m^2
Now, Volume of Triangular Pyramid = 1/3 x Area of Base x Height
= 1/3 x 14 x 5
= 1/3 x 70
= 23.33 m^2 or 23 1/3 m^2
You bought a gallon of milk for $5 and four boxes of cereal. You spent a total of $25.
How much did each box of cereal cost. *
Answer:
$5 is the answer.......
Answer:
one box cost is $5
Step-by-step explanation:
$25 - $5 = $20 - this is the cos of four cereal boxes
$20 / 4 = $5 each box cost
solve this i am not able to solve
Answer:
Step-by-step explanation:
First we need to set this ratio up in the coordinate plane. Because this is tangent, the 3 goes opposite the reference angle and the 4 goes along the x-axis, adjacent to the reference angle. We see that we are missing the third side of the triangle when we do this, namely the hypotenuse. We use Pythagorean's Theorem to find that this side is 5. Now we have to deal with the identities for each sin(2A) and cos(2A).
sin(2A) = 2sin(A)cos(A)
We know from the triangle we drew in the coordinate plane that
[tex]sin(A)=\frac{3}{5}[/tex] and [tex]cos(A)=\frac{4}{5}[/tex] so we fill in the formula accordingly and then simplify:
[tex]sin(2A)=2(\frac{3}{5})(\frac{4}{5})=\frac{24}{25}[/tex]
cos(2A) has 3 identities; I just picked the one I thought would be easiest to use and went with that one. Regardless of which one you pick you will get the same answer as long as you do the math correctly.
[tex]cos(2A)=cos^2(A)-sin^2(A)[/tex] and filling in the formula:
[tex]cos(2A)=(\frac{4}{5})^2-(\frac{3}{5})^2\\cos(2A)=\frac{16}{25}-\frac{9}{25}\\cos(2A)=\frac{7}{25}[/tex]
I'm not sure why you have 7/2 there...
x/3 + 3 = 4.Find the value of x
Answer:
3
Step-by-step explanation:
x/3 + 3 = 4
x/3 = 4 - 3
x/3 = 1
x = 3
Answer: x = 3
Step-by-step explanation:
Given
x/3 + 3 = 4
Subtract 3 on both sides
x/3 + 3 - 3 = 4 - 3
x/3 = 1
Multiply 3 on both sides
x/3 × 3 = 1 × 3
[tex]\boxed{x=3}[/tex]
Hope this helps!! :)
Please let me know if you have any questions
Find the area of this circle please…Use 3 for pi….Thanks
Answer:
the area of a circle is equal to pi r square that is 3.14×3×3 = 28.26.
Which is the better investment over ten years:
$20 000 at 12% compound interest or $30 000 at 8% compound interest?
Answer:
$30000at 8%compound interest
A 27-inch board is to be cut into three pieces so that the second piece is 3 times as long as the first piece and the third piece is 5 times as long as the first piece.
If x represents the length of the first piece, find the lengths of all three pieces
What is the length of the first piece?
Isa finished 30% of his homework in 27 minutes. How many more minutes will it take lsa to complete his homework, assuming that he works at the
same pace?
A А.
63 minutes
B
67 minutes
C
70 minutes
O
D
90 minutes
Answer:
The answer is A. 63 minutes.
Step-by-step explanation:
I added 27 minutes with each of the answer then multiplied the two added numbers by 30%
27 + 63 = 90 x 30% = 27 minutes (correct answer)
27 + 67 = 94 x 30% = 28.2 minutes (wrong answer)
27 + 70 = 97 x 30% = 29.1 minutes (wrong answer)
27 + 90 = 117 x 30% = 35.1 minutes (wrong answer)
The piecewise graph below is the ceiling function? True or false ?
Answer: The answer is true im taking that same test
It is TRUE because the piecewise graph shown is the ceiling function.
Simplify the algebraic expression: 16 - 4(3x - 5)
Answer:
23x
Step-by-step explanation:
16 - 4(3x-5)
12(3x-5)
36x-60