# Parallel Lines Cut by a Transversal

## Parallel Lines Cut by a Transversal

Here you are given line AB is parallel to line CF. With transversal GH intersecting line AB at point D and intersecting line CF at point E. Before you do anything else, does it appear that any of the numbered angles have any relationship between them? In your notebook write the word conjecture, and under the word conjecture, write any and all angle relationships that appear to be true to you, just by visually inspecting this diagram. (For example, does it appear any of the angles are supplementary or congruent?) After you write your conjectures into your notebook, go ahead and use the angle measure tool to find the angle measures of all 8 numbered angels. What do you notice? Use complete sentences to explain what you discovered after finding the angle measures of all 8 angles. (Make sure to write down which angles have equal measure to each other, and which angles are supplementary to each other.) Next, Grab either point A, point B, or point C, and drag it. What do you notice about the angle measures? Explain in your notebook using complete sentences what you notice after dragging one or more of the points.