# Same Side Interior Angles Theorem

- Author:
- Tim Brzezinski

- Topic:
- Angles, Straight Lines

In the applet below, a

**TRANSVERSAL**intersects**2 PARALLEL LINES**. When this happens, there are 2 pairs of**SAME-SIDE INTERIOR ANGLES**that are formed. Interact with the applet below for a few minutes, then answer the questions that immediately follow.**Directions & Questions:**1) Complete the following statement: I

**f a transversal intersects 2 ________________ ______________, then same-side interior angles are _____________________.**2) If the gray angle above measures 120 degrees, what would the measure of its same-side interior angle be? 3) As you moved the slider, what transformation(s) took place?