Question

Find the radius of the incircle of a triangle whose sides are 15, 20, 25.

answer in photo please ​

Answer 1

Step-by-step explanation:

The radius of the incircle is r = 5.

This is a right triangle because:

15^2 + 20^2 = 25^2

225 + 400 = 625

So the area of the triangle: A = a * b / 2 = 15 * 20 /

2 = 150

Also   A = r * s

s = ( a + b + c ) / 2 = ( 15 + 20 + 25 ) / 2 = 60 / 2 = 30

150 = r * 30

r = 150 : 30 = 5

hope you are understand:)