Question

What’s the unknown angle in the trapezoid?

Answer 1

The unknown angle a is 23°.

Solution:

Given image is a trapezoid.

In the trapezoid, opposite sides are parallel.

If two lines are parallel, then the corresponding angles are equal.

⇒ 67° + ∠a = 90°

Subtract 67 from both sides.

⇒ 67° + ∠a  - 67° = 90° - 67°

⇒ ∠a = 23°

The unknown angle a is 23°.