Answer:
If a transversal intersects two parallel lines, then same-side interior angles are supplementary.
Explanation:
If two angles add up to make a sum of 180 degrees, they are said to be supplementary angles. It is not necessary to be together for two angles to be supplementary. They can be separate and still add up to make a total of 180 degrees.
Likewise, the same-side interior angles will be called supplementary angles if a transversal intersects two of the parallel lines.