Question

In the given figure ∠PQR = 90° , PQ = 28cm , PR = 35 cm , Find QR. ​

Answer 1

Answer:

In triangle PQR ,

angle Q = 90°

By Pythagoras theorem,

PQ^2 + QR^2 = PR^2

28^2 + QR^2 = 35^2

QR^2 = 35^2 - 28^2. IDENTITY = A^2 - B^2 = ( A + B ) ( A - B )

QR^2 = (35 + 28) (35 - 28)

QR^2 = 63 * 7

QR^2 = 441

QR = √441

QR = 21