In fig. 2, a circle with centre O is inscribed in a quadrilateral ABCD such that, it touchesthe sides BC, AB, AD and CD at points P, Q, R and S respectively. If AB=29cm, AD=23,B= 90 and DS=5cm, then the radius of the circle (in cm.) is: Share with your friends Share 0 Somnath maths answered this Given,AB=29cm,AD=23cm, B=900,DS=5cm Join OP and OQ.Then,OP=OQ, OP⊥PB OQ⊥BQ ∴OPBQ is a square. Tangles from an external point,being equal,we have: DS=DR, BP=QB, AS=AP∴DS=DR=5cm∴AS=18cm [23−5] also AP=18cm PB=AB−AP =29−18 =11cm ∴OQ=11cm The radius is 11cm. 0 View Full Answer