Chapter 6 - The Circular Functions and Their Graphs - Chapter 6 Test Prep - Review Exercises - Page 644: 12

$${162^ \circ }$$

$$\eqalign{ & \frac{{9\pi }}{{10}} \cr & {\text{Multiply by }}\frac{{{{180}^ \circ }}}{\pi }. \cr & \frac{{9\pi }}{{10}}{\text{radians}} = \frac{{9\pi }}{{10}}\left( {\frac{{{{180}^ \circ }}}{\pi }} \right) \cr & {\text{Simplify}} \cr & \frac{{9\pi }}{{10}}{\text{radians}} = \frac{{{{1620}^ \circ }}}{{10}} \cr & \frac{{9\pi }}{{10}}{\text{radians}} = {162^ \circ } \cr} $$