Question

Complete the following activity to find the length of hypotenuse of right angled triangle, if sides of right angle are 9 cm and 12 cm.

Activity: In ∆PQR, m∠PQR = 90°

By Pythagoras Theorem,

PQ² + `square` = PR²    ......(I)

∴ PR² = 9² + 12² 

∴ PR² = `square` + 144

∴ PR² = `square`

∴ PR = 15

∴ Length of hypotenuse of triangle PQR is `square` cm.

Answer 1

In ∆PQR, m∠PQR = 90° 

By Pythagoras Theorem,

PQ² + QR² = PR²     ......(I)

∴ PR² = 9² + 12² 

∴ PR² = 81 + 144

∴ PR² = 225

∴ PR = 15      ......[Taking square roots of both sides]

∴ Length of hypotenuse of triangle PQR is 15 cm.