Question

use the figure to name the vertex of ∠1.
a) c
b) a
c) d
d) b

Explanation:

Step1: Recall the definition of the vertex of an angle

The vertex of an angle is the common endpoint of the rays that form the angle.

Step2: Identify the vertex of ∠1

Looking at the figure, for ∠1, the common endpoint of the rays forming it is point \(A\).

Answer:

B. \(A\)