Question

In ∆ ABC ∠A=∠C and BC = 4 then, the the perimeter of ∆ ABC is ………………….​

Answer 1

Answer:

By Pythagoras Theorem,

⇒ AC2 = AB2+ BC2

Given in ΔABC, AB = 3, BC = 4, AC = 5.

⇒ 52 = 32 + 42

⇒ 25 = 25

∴ ΔABC is a right angled triangle and ∠B is a right angle.

We know that the radius of the circle touching all the sides is (AB + BC – AC )/ 2

⇒ The required radius of circle = (3 + 4 – 5 )/2 = 2/2 = 1