Question

Two lines AB and CD intersect at O. If ∠AOC + ∠COB + ∠BOD = 270°Find the measures of ∠AOC, ∠COB, ∠BOD, ∠DOA.

Answer 1

all are 90°

Explanation:

Vertical angles are congruent, and linear angles are supplementary, so we have ...

∠AOC + ∠COB + ∠BOD = 270°

180° + ∠BOD = 270°

∠BOD = 90°

Since the lines cross at right angles, all of the angles are 90°.