Question

The length of a chord of a circle is $16cm$, which is at a distance of $6cm$ from the centre of the circle. Find the diameter of a circle.

Answer 1

Let the radius of the circle is $r$, then

$r^2=(\text{distance of the chord from the centre}{)}^2+(\text{half of the length of the chord}{)}^2$

$\Rightarrow r^2=6^2+8^2=36+64=100$

$\Rightarrow r=10$ cm

As we know, diameter is twice of radius,

$\therefore d=2\times 10=20$