In the given figure, MP is tangent to a circle with center A and NQ is a tangent to a circle with center B. If MP = 15 cm, NQ = 8 cm, PA = 17 cm and BQ = 10 cm, then AB is: |
28 cm 14 cm 13.5 cm 23 cm |
14 cm |
In right angled triangle PMA \( { AP}^{2 } \) = \( { PM}^{2 } \) + \( { AM}^{2 } \) = \( { 17}^{2 } \) = \( { 15}^{2 } \) + \( { AM}^{2 } \) = \( { AM}^{2 } \) = 289 - 225 = AM = \(\sqrt {64 }\) = 8 In right angled triangle BNQ \( { BQ}^{2 } \) = \( { BN}^{2 } \) + \( { NQ}^{2 } \) = \( { 10}^{2 } \) = \( { BN}^{2 } \) + \( { 8}^{2 } \) = \( { BN}^{2 } \) = 100 - 64 = BN = \(\sqrt {36 }\) = 6 As we know, AM = AC = 8 and BN = BC = 6 cm. Now, AB = AC + BC = AB = 8 + 6 = 14. |