Answer:
The rate of change in surface area when r = 20 cm is 20,106.19 cm²/min.
Step-by-step explanation:
The area of a sphere is given by the following formula:

In which A is the area, measured in cm², and r is the radius, measured in cm.
Assume that the radius r of a sphere is expanding at a rate of 40 cm/min.
This means that 
Determine the rate of change in surface area when r = 20 cm.
This is
when
. So

Applying implicit differentiation.
We have two variables, A and r, so:



The rate of change in surface area when r = 20 cm is 20,106.19 cm²/min.
Answer: 28
Step-by-step explanation:
Given
Kenny made 7 serves over the net for every 2 serves that did not go over the net i.e. success rate of Kenny is

for 36 serves, applying the same success rate, it is

Serves that did not make over the net is 
Thus, Kenny will make 28 serves that make over the net
There are many different types of equations we can use to allow x to equal 19! Below are some examples :) See if you can come up with some on your own based off of these examples:
5x = 95.....................................Divide both sides b 5
x = 19.......................................There's one for you :)
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1 + x - 5 = 15............................Combine like terms
x - 4 = 15..................................Add 4 to both sides
x = 19
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There's just a couple of examples, but see if you can come up with some on your own and let me know if you get stuck!
Thank you for your question! I hope this helped! Have an amazing day and feel free to let me know if I can help you any further! :D
Answer:
∠B = 12°
∠C = 180 - 48° = 132° ( straight line angle = 180)
Sum of angles of a triangle = 180°
180 = ∠A + ∠B + ∠C
180 = ∠A + 12 + 132
180 - 144 = ∠A
∠A = 36°
option B
Answer:
it is 13x=2
Step-by-step explanation:
i ran the math through my multipurpose calculator