LA5 marksYear: 2023HardCBSE Class 10
trianglessimilar-trianglesmediansSAS-similarityproof
Question
If AD and PM are medians of triangles ABC and PQR, respectively where △ABC∼△PQR, prove that PQAB=PMAD.
Solution
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Two similar triangles ABC and PQR with medians AD and PM respectively
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△ABC∼△PQR. AD and PM are medians of △ABC and △PQR respectively. ∴PQAB=QRBC
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PQAB=2QM2BD=QMBD
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Also ∠B=∠Q (△ABC∼△PQR). ⇒△ABD∼△PQM (SAS similarity)
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⇒PQAB=PMAD. Hence proved.
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