Given: QN = RN and MN=NP
Given: m∠1=m∠2
Since SN is perpendicular to MP.
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Given: MN=NP
• Therefore triangles QNM is similar to triangle RNP by the SAS Congruence Theorem.
• Since two corresponding sides are equal, the triangles are in fact equal triangles.
Thus, the length of the third corresponding sides QM and RP must also be equal by CPCTC.