### Home > APCALC > Chapter 7 > Lesson 7.1.4 > Problem 7-37

7-37.

As clumsy Kenny pours his cold coffee on the floor, he notices that the growing puddle is circular. Let be the area of a circle with radius

*at time*

*. Write an equation that relates*

*.*

Implicitly differentiate both sides of the area function WITH RESPECT TO TIME, .