Properties of Parallel Lines
In this investigation, you'll discover relationships among the angles formed when parallel lines are intersected by a third line, called a transversal.
Sketch and Investigate
1. Construct line AB and point C, not on line AB.
2. Construct a line parallel to line AB through point C.
3. Construct line CA. Drag points C and A to make sure the three lines are attached at those points.
4. Construct points D, E, F, G, and H as shown.