More Lessons for Grade 9

Math Worksheets

Videos, worksheets, games and activities to help Geometry students learn about the vertical angle theorem.

The Vertical Angle Theorem states that vertical angles are congruent.

Geometry - Proving Angles Congruent - Vertical Angles Theorem (P 1)

This video introduces the components of the structure of a good proof which includes: the given information, what needs to be proved and a diagram of the information. It discusses and proves the vertical angle theorem.

All of the proofs in this lesson are of the paragraph variety.

Along with the vertical angle theorem, this two part video series discusses the congruent supplements theorem, the congruent complements theorem, and all right angles are congruent theorem.

There are a number of proofs that are completed in the same way, hopefully by the end of the second video, you will be able to complete similar proofs yourself.

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