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: |
13 11 15 12 |
13 |
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. |