A chord is at a distance of 8 cm from the centre of a circle of radius 17 cm. The length of the chord is
(a) 25 cm
(b) 12.5 cm
(c) 30 cm
(d) 9 cm
let, the chord intersects the circle at A & B.
O be the center of the circle.
Draw a perpendicular form center O i.e. OD
Join OB & OA
In tri ODA,
L ODA = 90
By Pythagoras theorem
OB2=OD2+DB2
172=OD2+82
OD=15
Length of chord=OA+OD=2OA=2 x 15=30cm
Hence, option c is correct