Question

calculate the length of tangents from a point 15cm away from the centre of a circle of radius 9cm

Answer 1

distance from centre=15 cm
radius=9 cm
tangent will be =12 cm

Answer 2

Answer:

Angle between Tangents and radii are always 90°

Therefore,

By Pythagoras theorem

Radius²+ tangent²=distance of external point²

9²+tangent²=15²

81+tangent²=225

Tangent²=225-81

Tangent²=144

Tangent=√144

Tangent=12cm

So the length of tangents are 12cm

Answer 3

Answer:

Angle between Tangents and radii are always 90°

Therefore,

By Pythagoras theorem

Radius²+ tangent²=distance of external point²

9²+tangent²=15²

81+tangent²=225

Tangent²=225-81

Tangent²=144

Tangent=√144

Tangent=12cm

So the length of tangents are 12cm