In the diagram, PO and OR are radii, |PQ| = |QR| and reflex < PQR is 240o. Calculate the value x
A. 60o B. 55o C. 50o D. 45o
Correct Answer: A
Explanation
< Q = \(\frac{240}{2}\) (angle at centre twice that at the circumference) < Q = 120o Also < POR = 360 - 240 = 120o ( < s at centre) since /PQ/ = /QR/, < x = < R Byt < x + < R + O + Q = 360 (sum of interior < s of quadrilateral) x + R + 120 = 360o x + R = 360 - 240 = 120; Since x = R x + x = 120 2x = 120 Since x = R x + x = 120 2x = 120 x = \(\frac{120}{2}\) = 60o
