Question

ABC is an isosceles right triangle,right angled at C.Prove that AB^2=2AC^2

Answer 1

By Pythagoras theorem
AB^2=AC^2+BC^2.............1
since it is isosceles ∆
So AC=BC
→1→AB^2=2AC^2

Answer 2

Triangle ABC, right angled at C.
.:. Equal sides are AC and BC.
    And hypotenuse is AB
By Pythagoras theorem :-
(hypotenuse)^2 = (Perpendicular)^2 + (Base)^2
AB^2 = AC^2 + BC^2
AB^2 = AC^2 + AC^2     (AC = BC)

AB^2 = 2AC^2

I hope this will help u.........