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Triangle similarity review

Review the triangle similarity criteria and use them to determine similar triangles.

What are the triangle similarity criteria?

AATwo pairs of corresponding angles are equal
Two triangles. One triangle is smaller than the other. Both triangle have two angles that are congruent.
SSSThree pairs of corresponding sides are proportional
Two triangles. One triangle is smaller than the other. The smaller triangle has side lengths a, b, and c. The larger triangle has side lengths a times k, b times k, c times k.
SASTwo pairs of corresponding sides are proportional and the corresponding angles between them are equal
Two triangles. One triangle is smaller than the other. The smaller triangle has side lengths a and b. The larger triangle has side lengths a times k and b times k. The angle between the side lengths of the smaller triangle is congruent to the angle between the side lengths of the larger triangle.
Want to learn more about the triangle similarity criteria? Check out this video.

Check your understanding

Problem 1
Three triangles labeled A, B, and C. Triangle A has a forty-six degree angle and a seventy-nine degree angle. Triangle B has a fifty-one degree angle and a sixty-two degree angle. Triangle C has a forty-six degree angle and a seventy-nine degree angle.
Which triangle is similar to triangle A?
Choose 1 answer:

Want to practice more problems like this? Check out this exercise for the AA criterion and this exercise for the SSS criterion.

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