### Home > INT2 > Chapter 8 > Lesson 8.2.2 > Problem8-39

8-39.

A regular polygon has an interior angle measuring $135°$. How many sides does it have? Determine the number of sides using two different strategies. Show all work. Which strategy was most efficient? Homework Help ✎

Use the formula in the Math Notes box.

$135°=\frac{180°(n-2)}{n}$

What is the measure of an exterior angle? The exterior angles of a regular polygon sum to $360°$.