Question

some side interior angles
the green arcs show a pair of same side interior angles.
drag the two black points to show another pair.
same side interior angles are:
check your work: keep trying.
check your angle - pair
congruent (same size)
supplementary (different size)

Explanation:

Step1: Recall angle - pair property

Same - side interior angles formed by two parallel lines and a transversal add up to 180 degrees.

Step2: Define supplementary angles

Two angles are supplementary if the sum of their measures is 180 degrees.

Answer:

Supplementary (different size)