Question

Find the length of the tangent to a circle of radius 3 cm at a point from a distance of 5cm from the centre

Answer 1

Refer attachment for figure .

we will use Pythagoras theorem.

Let AB be tangent .

$\tt{ {ab}^{2} } = {ob}^{2} - {oa}^{2}$

$\tt \: ab = \sqrt{25 - 9}$

$\tt \: ab = \sqrt{16}$

${ \tt \boxed{ ab = 4cm}}$