Q21 of 93 Page 10

In Fig. 10.59, AB is a cord of length 16 cm of a circle of radius 10 cm. The tangents at A and B intersect at a point P. Find the length of PA.


OA=10 cm


Perpendicular from centre to the chord bisects the chord.


So AM=MB=8cm


Using Pythagoras theorem in triangle AOM



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