Q9 of 93 Page 10

If PA and PB are tangents from an outside point P. such that PA = 10 cm and . Find the length of chord AB.


Given: PA and PB are tangent of a circle PA= 10 cm and angle APB= 60o


Let O be the center of the given circle and C be the point of intersection of OP and AB


In triangle PAC and triangle PBC


PA = PB (tangent from an external point are equal)


APC =BPC (tangent from an external point are equally inclined to the segment joining center to the point)


PC =PC (common)



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