Question

In a right angled triangle ABC right angled at B, BC= 15 cm and AB= 8 cm. A circle is inscribed in triangle ABC. Find the radius of a circle.​

Answer 1

AC=root 15^2+8^2

=root 225+64

=root 289

=17cm

let I be the centre of the circle

and D be a Point on BC such that ID perpendicular to BC.

F be a point on AB such that IF perpendicular to AB.

Now, so BDIF is a square.

And BD=BF.

2(a+b+c)=15+17+8

a+b+c=40/2

=20

Therefore, a=3, b=12, c=5

Therefore radius, IF= ID= IE=3CM...