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Find the length of the hypotenuse of a right angled triangle if remaining sides are 9 cm and 12 cm.

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#### Solution

Let ∆PQR be the given right-angled triangle.

In ∆PQR, ∠Q = 90°

∴ PR^{2} = PQ^{2} + QR^{2} .......[Pythagoras theorem]

= 9^{2} + 12^{2 }

= 81 + 144

= 225

∴ PR = `sqrt(225)` .....[Taking the square root of both sides]

= 15 cm

∴ The length of the hypotenuse of the right-angled triangle is 15 cm.

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