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Prove triangle properties


Liliana tried to prove that M, N, equals, M, P in the following diagram.
Triangle M N P. Angle M is fifty degrees. Angle N is sixty-five degrees. Angle P is sixty-five degrees.
1m, angle, M, N, P, equals, m, angle, M, P, N, equals, 65, degreeGiven
2Construct altitude M, Q.
3m, angle, M, Q, N, equals, m, angle, M, Q, P, equals, 90, degreeDefinition of altitude
4triangle, M, Q, N, \cong, triangle, M, Q, PAngle-angle-side congruence
5M, N, equals, M, PCorresponding sides of congruent figures have equal lengths.
What was the first mistake in Liliana's proof?
Choose 1 answer: