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प्रश्न
Find the unknown side in the following triangles
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उत्तर
From ∆PQR, by Pythagoras theorem.
PR2 = PQ2 + QR2
342 = y2 + 302
⇒ y2 = 342 – 302
= 1156 – 900
= 256 = 162
y2 = 162
⇒ y = 16
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