Problem preview
G-CO.11 Warmup M2-035-A02-V01

Prove parallelogram theorems and their converses, including diagonal and rectangle results.

Use opposite angles in a parallelogram to find a missing angle or solve for a variable

Problem

In parallelogram \(ABCD\), angle \(A=72^{\circ}\). Find the missing angle measure.

Big Picture

What this problem is really about

Opposite and adjacent angle pairs in a parallelogram use different relationships, so position must come before arithmetic. We’ll locate the requested vertex across from the given one, transfer the measure through congruence, and use a neighboring supplementary angle only as a check.

Inside Gozunta

Turn the preview into practice.

More than a preview

Gozunta lets you study this problem—and more than 10,000 others.

Create targeted learning sessions, use hints, check your answer, read the walkthrough, watch the video, print the work, and track your progress.

Discover Gozunta Try it now
Four variants of this problem type
Curriculum context
Course
Math II
Standard
G-CO.11
Category
Geometry
Domain
Congruence
Objective
Prove parallelogram theorems and their converses, including diagonal and rectangle results.
Problem type
Use opposite angles in a parallelogram to find a missing angle or solve for a variable