Question Video: Finding the Measure of an Angle in a Parallelogram given the Opposite Angle’s Measure Mathematics

Video Transcript

Given that 𝐴𝐵𝐶𝐷 is a parallelogram and the measure of angle 𝐶 equals 68 degrees, find the measure of angle 𝐴.

We can begin by recalling that a parallelogram is defined as a quadrilateral with both pairs of opposite sides parallel. We can see that the parallel line segments are already marked on the diagram. We are considering the angles in this parallelogram. So let’s recall one of the angle properties of a parallelogram that may be useful here.

We know that opposite angles in a parallelogram are equal in measure. And the angle that we need to determine, the measure of angle 𝐴, is opposite the angle 𝐶, whose measure we are given. Since opposite angles are equal in measure, then we can write that the measure of angle 𝐴 equals the measure of angle 𝐶. And as angle 𝐶 has a measure of 68 degrees, then so does angle 𝐴. We can give the answer that the measure of angle 𝐴 equals 68 degrees.