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Why are corresponding exterior angles of similar triangles congruent?

because the sum of the measures of the interior angles of a triangle always equal 90°, so the sum of the measures of the exterior angles must always be the same

B
because the sum of the measures of the interior angles of a triangle always equal 180°, so the sum of the measures of the exterior angles must always be the same

C
because corresponding interior angles are congruent, and the sum of the measures of an interior angle and an adjacent exterior angle always equals 90°

D
because corresponding interior angles are congruent, and the sum of the measures of an interior angle and an adjacent exterior angle always equals 180°

2 Answers

10 votes

Final answer:

Corresponding exterior angles of similar triangles are congruent because the sum of an interior angle and its adjacent exterior angle in a triangle is always 180 degrees, and similar triangles have equal corresponding angles.

Step-by-step explanation:

The reason why corresponding exterior angles of similar triangles are congruent is because corresponding interior angles are congruent due to triangles' similarity, and the sum of the measures of an interior angle and its adjacent exterior angle always equals 180°.

This is based on the concept that the exterior angle of a triangle is equal to the sum of the two non-adjacent interior angles. Since similar triangles have the same angle measures, their corresponding exterior angles must also be congruent.

User Charles Langlois
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Answer:

If two pairs of corresponding angles in a pair of triangles are congruent, then the triangles are similar. We know this because if two angle pairs are the same, then the third pair must also be equal. ... Thus, they always form similar triangles.

User Physiker
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