Video Transcript
Work out the value of 𝑥 in the
figure.
First of all, let’s think about the
type of lines we’re seeing in the figure. We have two parallel lines that are
cut by a transversal, which makes the 61-degree angle and the 𝑥-angle alternate
interior angles. And when two parallel lines are cut
by a transversal, alternate interior angles are congruent. This means both of these angles are
equal in measure and 𝑥 must be equal to 61.