Conditions for Parallel Lines
- Azucena Overman
Use the sliders to change the angle. If the two blue lines intersect, then the triangle will be shaded. Zoom out to see the other point of the triangle for really skinny triangles. To zoom out, click on the first button and select the Zoom Out tool. Then click on the image to zoom out. You can also drag point A by clicking on the arrow tool and then clicking and dragging the point.
What does it mean when the two blue lines don't make a triangle? What type of relationship is there between the green and purple angles when you can't make a triangle?