Question

∠1 and ∠2 can best be described as -
vertical angles
right angle
straight angle
bisected angle

Explanation:

∠1 and ∠2 share a common side and vertex, and their non-common sides form a straight line, meaning their measures add up to 180°. A straight angle is 180°, and angles that form this are supplementary, which matches the pair ∠1 and ∠2. Vertical angles are opposite each other, right angles are 90°, and bisected angles are split into equal parts, none of which apply here.

Answer:

straight angle