Which expression gives the measure of angle RST in the diagram below?
Check the final answer first, then review the worked steps.
Step-by-step solution
The angle $\angle RST$ is an exterior angle to the circle. Its measure is half the difference of the intercepted arcs. The intercepted arcs are $162^{\circ}$ and $38^{\circ}$.
Answer
$$\frac{1}{2}(162^{\circ} - 38^{\circ})$$