A circle is inscribed in a quadrilateral ABCD, touching sides AB, BC CD and DA at P, Q, R and S, respectively. If AS = 6 cm, BC = 12 cm, and CR = 5 cm, then the length of AB (in cm) is:
Answer & explanation
Correct answer: option 1
CR = CQ = 5 cm
BQ = BC - CQ
= 12 - 5 = 7 cm
BQ = BP = 7 cm ...(1)
AS = AP = 6 cm ..(2)
Adding equation (1) and (2), we get
= 7 + 6
= 13 cm
Therefore, length of AB is 13 cm.