Answer:
The correction answer is y = - 2
Step-by-step explanation:
10-5y=20
-5y=10
y=10/-5
y=-2
A radioactive substance with initial value of 800g decays according to the exponential model A= 800e^(kt). After 10 years, only 400g of the substance remains. Find the value of k. Round your answer to the nearest thousandth. NO LINKS!!!!
Answer:
k ≈ - 0.069
Step-by-step explanation:
Given
A = 800 [tex]e^{kt}[/tex]
Substitute A = 400 and t = 10 into the equation
400 = 800 [tex]e^{10k}[/tex] ( divide both sides by 800 )
0.5 = [tex]e^{10k}[/tex] ( take the ln of both sides )
ln [tex]e^{10k}[/tex] = ln0.5
10k lne = ln0.5 [ lne = 1 ]
10k = ln 0.5 ( divide both sides by 10 )
k = [tex]\frac{ln0.5}{10}[/tex] ≈ 0.069 ( to the nearest thousandth )
Answer:
Step-by-step explanation:
400 = 800 * e^(k*t)
What are the units of t? I'm taking it as years.
Divide by 800
400/800 = e^(k*10)
1/2 = e^(k*10)
ln(1/2) = ln(e)^(k*10)
ln(1/2) = k*10 * ln(e)
ln(e) = 1
-0.69314 = k*10
-0.069314 = k
Check
A = 800 e^(-0.069314*10)
A = 800 e^(-0.69314)
A = 800 * 0.50000359
A = 400.0028722
Which is close enough to 400
A bag contains eight white marbles, six red marbles and four blue marbles.
How many blue marbles must be added to the bag so that the probability
of choosing a blue marble is 1/2?
a. 6
b. 5
c. 10
d. 0
Answer:
c) 10
Step-by-step explanation:
you need to add the white and red marbles which would be 14.
then you subtract 14 by the amount of blue marbles.
Solve for x.
x + 2 over 4 = 8
[tex]\huge\text{Hey there!}[/tex]
[tex]\mathsf{\dfrac{x +2}{4}=8}[/tex]
[tex]\large\textsf{MULTIPLY 4 to BOTH SIDES}[/tex]
[tex]\mathsf{\dfrac{x +2}{4}\times4=8\times4}[/tex]
[tex]\large\textsf{CANCEL out: 4}\times\large\textsf{4.}[/tex]
[tex]\large\textsf{KEEP: 8}\times\large\textsf{4 because it helps you solve for x}[/tex]
[tex]\mathsf{8\times4=\bf 32}[/tex]
[tex]\large\text{New equation: \textsf{x + 32 = \bf 32}}[/tex]
[tex]\large\textsf{x + 2 = 32}[/tex]
[tex]\large\textsf{SUBTRACT 2 to BOTH SIDES}[/tex]
[tex]\mathsf{x +2-2=32-2}[/tex]
[tex]\large\textsf{CANCEL out: 2}-\large\textsf{2 because that gives you 0}[/tex]
[tex]\large\textsf{KEEP: 32}-\large\textsf{2 because that helps you solve for x}[/tex]
[tex]\large\textsf{New EQUATION: \mathsf{x = 32 - 2}}[/tex]
[tex]\mathsf{x = 32 - 2}[/tex]
[tex]\large\textsf{Simplify above and you have your result to this equation}[/tex]
[tex]\mathsf{32-2=\bf 30}[/tex]
[tex]\boxed{\boxed{\large\textsf{Answer: \huge \bf x =30}}}\huge\checkmark[/tex]
[tex]\large\text{Good luck on your assignment and enjoy your day!}[/tex]
~[tex]\frak{Amphitrite1040:)}[/tex]
How do the angles and side lengths of the preimage relate to the corresponding angles and side lengths of the image of a dilation with a scale factor not equal to 1?
Answer:
The angles are proportional and the side lengths are proportional.
Step-by-step explanation:
Savaas Realize
Help me guys find the solution please and thank you
4x+17=23
write the percent of each figure
that is shaded.
Answer:
1. 21% 2. 70%
Step-by-step explanation:
1. 21 out of 100 are filled in
2. 7/10 are filled in
Jovi distributed 3(n+2) and got 3 x n + 3 x 6 is his answer correct
Answer:
Step-by-step explanation:
since 3 is outside the parenthesis (n + 2) you multiply the 3 by the n and the 2 and
3n + 6
next subtract the 6 and add the 6 to the other side
3n - 6 = 6
3n = 6
n = 2
In the diagram below, xy and z are tangent to 0. What is the measure of XZ?
Answer:
A. 130°
Step-by-step explanation:
Answer:130
Step-by-step explanation:
I just finished the quiz :)
which equation is not a linear function:
y=2x
y=x+2
y=x-2
y=x²
Answer:
Step-by-step explanation:
A linear equation can be written in the form
y = mx+b.
y = x² is not linear.
Evaluate each series.
Help pls 50 points
Answer:
1. 2,555
2. 23.25
Step-by-step explanation:
1. 5+10+20+...
S9 = 5(2^9-1)/(2-1)
= 5(511) = 2,555
2. 12+6+3+1.5+0.75 = 23.25
HELP WITH THIS ASAP!
Answer:
Hi, there your answer will C. 85pi ft^2
Step-by-step explanation:
pi(5)(12)+pi(5)^2
60pi+25pi
85pi ft^2
Hope this helps :)
Qu
Peter hired a cleaning company to clean his house. The cleaning company charges a
fixed fee of $15 plus $17 per hour to clean a house.
a. Write an equation that can be used to determine, c, the total amount in dollars that
the cleaning company charges to clean a house in h hours.
To find the total cost you need to multiply the hourly rate by the number of hours they work and add the fixed fee.
C = 17h + 15
Giving brainliest ; What is the mean of the data set? {20,1,14,14,9,8} Enter your answer in the box.
Answer:
11
Step-by-step explanation:
(20 + 1 + 14 + 14 + 9 + 8) / 6
= 66 / 6
= 11
I think it’s 393.75 But not Sure can anyone confirm ? Or share the right answer
Answer:
$415.63
Step-by-step explanation:
it would have been 393.75, but he worked 5 hours overtime and got paid time and a half for it, meaning his normal pay plus half of it. (only for overtime tho).
so first calculate his normal pay:
40 × 8.75 = 350
then add overtime to it
8.75 × 5 = 43.75
43.75 × 1.5 = 65.625
65.625 + 350 = 415.625
round that and its 415.63!
Nine years ago, Tarah opened a savings account with her bank. She started with a balance of $359 and has not made any withdrawals or deposits since then. If her interest rate is 8% each year, how much interest has accrued using simple interest?
What is Tarah's new total balance?
Answer:
$258.48
Step-by-step explanation:
Matthew has a bag that contains orange chews, cherry chews, and lime chews. He
performs an experiment. Matthew randomly removes a chew from the bag, records
the result, and returns the chew to the bag. Matthew performs the experiment 24
times. The results are shown below:
A orange chew was selected 10 times.
A cherry chew was selected 11 times,
A lime chew was selected 3 times.
Answer: 13/24
Step-by-step explanation:
The experiment occurred 24 times orange or lime was selected 10+3=13
Probability the next chew will be orange or lime: 13/24
Find the surface area and volume of the figure. Round to the nearest tenth.
Hurry. !!! The formula A = 6s' gives the surface
area A of a cube with a side length s.
What is the surface area of a cube that
has a side length of 5 inches?
A. 25 square inches
B. 125 square inches
C. 150 square inches
D. 300 square inches
5th grade math. correct answer will be marked brainliest
The answer is b
saddsadsadas
Answer:
B
Step-by-step explanation:
Cause he added 24.76 more pounds to the 3.6 pounds. So you can take 24+3=27 and you might think C, but 0.76+0.6 that equals more than 1, so 27+1=28, and B has 28 as its answer, so its B
B
2. Use the image to answer the questions.
(a) What is the center and the radius of the circle?
(b) What are the equations of the circle in graphing form and in general form? Show your work.
Answer:
Center = (-1, 1)
Radius = 3
Graphing form
(x + 1)² + (y - 1)² = 3²
General form
x² + y² + 2x - 2y - 7 = 0
Step-by-step explanation:
Center = (-1, 1)
Radius = 3
Graphing form
(x + 1)² + (y - 1)² = 3²
General form \Expand graphing form\
(x² + 2x + 1) + (y² - 2y + 1) - 9 = 0
Rearrange
x² + y² + 2x - 2y - 7 = 0
Divide. Give the quotient and remainder.
33 - 8
:))))
1. The ages of customers at a store are normally distributed with a mean of 45 years and a standard deviation of 13.8 years.
(a) What is the z-score for a customer that just turned 25 years old? Round to the nearest hundredth.
(b) Give an example of a customer age with a corresponding z-score greater than 2. Justify your answer.
Part (a)
The raw score is x = 25. The mean and standard deviation are mu = 45 and sigma = 13.8 respectively.
The z score is computed with the formula below
z = (x-mu)/sigma
z = (25-45)/13.8
z = -1.449275 approximately
z = -1.45 is the final answer
========================================================
Part (b)
We want the z score to be larger than 2. So z > 2.
This is the same as wanting the expression (x-mu)/sigma to be larger than 2
(x-mu)/sigma > 2
(x-45)/13.8 > 2
x-45 > 2*13.8
x-45 > 27.6
x > 27.6+45
x > 72.6
If a customer's age is greater than 72.6 years, then this means they have a z score greater than 2. We can say they are more than 2 standard deviations above the mean.
If you need a whole number, then I'd round up to 73. Or you could pick any age larger than this.
Find the distance of the two given points (1,5) and (4,10)
Answer:
5.831
Step-by-step explanation:
Distance between both given points=Lenght=5.831
A bank is offering 3.5% simple interest on a savings account. If you earned $525 in interest
in 2 years, how much did you deposit in the savings?
O $7,500
O $8,000
O $7.250
$7.000
Answer:
$7500
Step-by-step explanation:
Given
[tex]I = 525[/tex]
[tex]R = 3.5\%[/tex]
[tex]T =2[/tex]
Required
The Principal
This is calculated using:
[tex]I =PRT[/tex]
Make P the subject
[tex]P = \frac{I}{RT}[/tex]
So, we have:
[tex]P = \frac{525}{3.5\% * 2}[/tex]
[tex]P = \frac{525}{7.0\%}[/tex]
[tex]P = 7500[/tex]
please help, no links
Answer:
150
Step-by-step explanation:
Remark
The exterior angle = the sum of the two given interior angles. The first job is to solve for x and then use that to find the exterior angle.
Equation
83 + 6x + 7 = 15x
Solution
Combine like terms
90 + 6x = 15x Subtract 6x from both sides.
6x 6x
90 = 9x Divide both sides by 9
90/9 = 9x/9
x = 10
Now the exterior angle = 15x
Exterior angle = 15*10
Exterior angle = 150
3) 40% of the class of 30 students are boys.
How many are girls?
Answer:
there 18 girls
Step-by-step explanation:
40% of 30 = 12
this means there are 12 boys
30-12 = 18
there 18 girls
Select the correct answer. Which function is represented by this graph
Answer:
A
Step-by-step explanation:
the point is at positive 8 and none of the other answers have positive 8
Which angle has a positive measure?
Answer:
what angles
Step-by-step explanation:
i do not see anything to solve
I will go potty now thx
Based on the stated expectations of the sit-and-reach test, which of the following is TRUE?
A.
Men are generally more flexible than women.
B.
Women are generally more flexible than men.
C.
Men and women are about equally flexible.
D.
No broad conclusions can be drawn about flexibility.
Answer:
B
Step-by-step explanation: