### Home > CCA2 > Chapter 7 > Lesson 7.1.4 > Problem 7-55

7-55.

The measure of ∠*ROS* in Δ*ROS* below is 60°. Homework Help ✎

The curved arrow represents the rotation of

, beginning from the positive *x*-axis. Through how many degrees hasrotated? If

*OR*= 1, what are the*exact*length of*OS*and*SR*?What are the

*exact*coordinates of point*R*?

Remember that a whole circle is 360°.

Remember the 30°-60°-90° triangle.