Question

Angle RST measures 80 degrees. Ray SU bisects the angle. What is the measure of the two smaller angles? Choices 20, 40, 80, 160

Answer 1

Given that a segment bisects an angle, we don't need to have the diagram to know that the larger angle is split into two equal angles (definition of an angle bisector).

Therefore, each smaller angle will measure just half of the larger angle.
$\frac{80}{2}=40$

ANSWER: Each smaller angle measures 40 degrees.