Q18 of 25 Page 627

In a ∆ABC, if , show that the triangle is isosceles.

Given:


Need to prove: ∆ABC is isosceles.



⇒


⇒ [Squaring both sides]


⇒


We know,


Therefore,


So,


⇒


⇒


That means a and b sides are of same length. Therefore, the triangle is isosceles. [Proved]


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