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Question
In the right-angled ∆PQR, ∠ P = 90°. If l(PQ) = 24 cm and l(PR) = 10 cm, find the length of seg QR.
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Solution
In the right-angled triangle PQR, ∠P = 90°. Hence, side QR is the hypotenuse.
According to Pythagoras' theorem,
l(QR)2 = l(PQ)2 + l(PR)2
⇒ l(QR)2 = (24)2 + (10)2
⇒ l(QR)2 = 576 + 100
⇒ l(QR)2 = 676
⇒ l(QR)2 = (26)2
⇒ l(QR) = 26
∴ Length of seg QR = 26 cm.
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