Measurements for Similar Triangles

This video shows how to find measurements for similar triangles. For example, two pentagons are represented as such: ABCDE ~ FGHIJ. If the angles ABC, GHJ, BCD, HJK, DEA measure 120°, 100°, 100°, 120°, and 140°, respectively, what are the measures of the remaining angles? You need to use the Polygon Angle Sum Theorem, which states that n-2×180 is equal to the sum of the measures of the angles of any polygon. Doing this will tell you that every pentagon has 540°. Find the missing angle by adding the angles you have together and subtracting the total from 540.


Provided by: Mometrix Test Preparation

Last updated: 02/19/2018
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