### Home > CALC > Chapter 5 > Lesson 5.1.4 > Problem 5-39

5-39.

You are being asked to 'minimize' perimeter. Did you recognize that this is an optimization problem?

The first thing you will do is build a geometric equation that represents the situation. Then you will apply Calculus.

What do we know?

Now that we have an equation, *P*(*h*), let's find it's minimum value.

*P* '(*h*) = ___________________

To find the *h*-value of the max and min, set *P* ' (*h*) = 0, and solve for *h*.

Then, for a complete answer, don't forget to find the corresponding value of *b*.