CCSS IP Math I 5.1.1 Example 4

Author:: Walch Education, GeoGebra Materials Team

Given the following:

Are

and

parallel? Are

and

parallel?

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and intersect at the same angle and . will never cross . Therefore, is parallel to .
and intersect at the same angle, but . As you move from to on , you move closer to, and will eventually intersect . Therefore, is not parallel to .