Question Analysis
This question involves the concept of an angle bisector.
Key Concept Explanation
An angle bisector is a ray that divides an angle into two equal - measure angles. So, the measure of the original angle is twice the measure of either of the sub - angles created by the bisector.
Step - by - Step Solution
1. Recall the property of an angle bisector. Since ray bisects , we know that .
2. Given that , then