Applying the Properties of a Parallelogram

In this video, you will learn the six important properties of parallelograms and how to apply them. A parallelogram is a quadrilateral with both pairs of opposite sides parallel. Remember, a quadrilateral is a four-sided figure. Click the player button to begin.

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Applying the Properties of a Parallelogram

Given: Parallelogram HJKL

What is the measure of angle HKL?

Read below to learn one strategy to find the unknown angle measure.

Step 1: Focus on Triangle HJK.

The sum of the measures of the angles of a triangle equals 180°. Therefore, the measure of angle JHK equals 30°.

Step 2: Focus on alternate interior angles.

The opposite sides of a parallelogram are parallel. Recall that if parallel lines are intersected by a transversal, then the alternate interior angles are congruent. So, the measure of angle JHK is equal to the measure of angle HKL. Therefore, the measure of angle HKL equals 30°.

 

Parallelograms Review

Now that you have learned about parallelograms, review your knowledge in this interactivity. Click the player button to get started.