Match each expression to its simplest form
(6r+7)+(13+7r)
(13 - 3/2 r) - (1 - r)
(-8 - r) + (2r - 4)
(7r - 3/2) -(2/3 + 6r)

12 - 1/2 r →
r - 13/6 →
13r+20 →
—12+r →

The radius of the base of a cylinder is 10 centimeters, and its height is 20 centimeters. a cone is used to fill the cylinder with water. the radius of the cone's base is 5 centimeters, and its height is 10 centimeters.

Acylinder has volume 45π and radius 3. what is it’s height?

How is working backward similar to solving an equation?