Question

Write an expression for the volume of a cylinder with a height 7in. greater than the radius.

Answer 1

First look up the formula for volume of a cylinder.

Answer 2

V = pi*r^2*h

Answer 3

The height is 7 in greater than the radius. How would you write that expression?

Answer 4

x + 7

Answer 5

So put that in to your equation.

Answer 6

pi*r^2*(x + 7)

Answer 7

Be sure to be consistent with your variables. The height is in relation to the length of the radius.

Answer 8

so change the x to a r?

Answer 9

That is what I would do. It really doesn't matter which one you use as long as you are consistent.

Answer 10

so it would read pi*r^2*(r + 7)

Answer 11

Yes, but you probably need to simplify.

Answer 12

how?

Answer 13

Distribute.

Answer 14

how

Answer 15

Multiply the term outside the parenthesis by each of the terms inside the parenthesis.

Answer 16

pi*r^3+7r^2?

Answer 17

Exactly.

Answer 18

thanks alot!

Answer 19

Your welcome.