It can be observed that RQ is the diameter of the circle. Therefore, ∠RPQ will be 90º.
By applying Pythagoras theorem in ΔPQR,
RP2 + PQ2 = RQ2
(7)2 + (24)2 = RQ2
Radius of circle,
Since RQ is the diameter of the circle, it divides the circle in two equal parts.
Area of ΔPQR = 1/2 x PQ x PR
=1/2 x 24 x 7
= 84 cm2
Area of shaded region = Area of semi-circle RPQOR − Area of ΔPQR