http://www.naviom.com/education/cbse-class-x-hots-questions-of-mathematics-circles/ CIRCLESA circle touches the sides of a quadrilateral ABCD at P, Q, R and S respectively. Show that the angles subtended at the centre by a pair of opposite sides are supplementaryIn figure, XP and XQ are tangents from X to the circle with centre O. R is a point on the circle. Prove that XA+AR=XB... Sat, 06 Mar 2010 22:32:17 IST en