Question

The quadrilateral is a parallelogram. Find the measure of angles 1, 2, and 3.

80°
Angle 1 measures______
degrees, angle 2 measures______
degrees, and angle 3 measures______
degrees.

Answer 1

1. 100°
2. 80°
3. 100°

Explanation:

You are given a parallelogram with one acute angle measuring 80°, two obtuse angles (1, 3) and another acute angle (2). You want to know the measures of the numbered angles.

Angle relations

In a parallelogram, adjacent angles are supplementary, and opposite angles are congruent.

∠1 = ∠3 = 180° -80° = 100°

∠2 = 80°