# Solution to Parallel Lines & Angles Problem

- Author:
- Tim Brzezinski

- Topic:
- Angles, Straight Lines

In the applet below, the black lines are parallel.
Interact with this applet for a few minutes, then answer the questions that follow.
As you do, be sure to move the

**BIG GREEN POINT**anywhere you'd like!**Questions:**1) How does the measure of the indicated angle relate to the measures of the

**pink angle**and the

**blue angle?**2) What previously learned theorem justifies this fact? Explain in detail.