**Vertical Angles and Parallel Lines Crossed by a Transversal** is the fourth of eight self-paced lessons in the “Lines, Angles, and Triangles” section of KET’s *GED ^{®} Geometry Professional Development Online Course*. This lesson establishes the basis for understanding the relationship between vertical and congruent angles when depicted in line drawings.

NOTE: This course was created based on the 2002 GED^{®} math test. The geometry instruction in this course is still valid, however, for up-to-date information about the 2014 GED^{®} math test, please visit KET’s GED^{®} Test Info: Mathematics online course.

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