In the given figure, AB and AC are tangents to a circle with centre O and radius 8 cm. If OA = 17 cm, then the length of AC (in cm) is
(a) 9 (b) 15 (c) √353 (d) 25
given,
OA = 17 cm
OB = 8 cm
by pythagoras theorem,
AB2+OB2=OA2
AB2=289−64
AB2=225
AB = 15