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Prove triangle properties

Problem

Liliana tried to prove that MN=MP 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.
StepStatementReason
1mMNP=mMPN=65°Given
2Construct altitude MQ.
3mMQN=mMQP=90°Definition of altitude
4MQNMQPAngle-angle-side congruence
5MN=MPCorresponding sides of congruent figures have equal lengths.
What was the first mistake in Liliana's proof?
Choose 1 answer:
Stuck?
Stuck?