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

**Solution:**

We know that, in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides.

In ΔABC, ∠ACB = 90° and AC = BC [Since, ABC is an isosceles triangle right angled at C]

Using Pythagoras theorem,

⇒ AB^{2} = AC^{2} + BC^{2}

⇒ AB^{2} = AC^{2 }+ AC^{2 } [Since AC = BC]

Therefore, AB^{2} = 2 AC^{2}

**☛ Check: **NCERT Solutions for Class 10 Maths Chapter 6

**Video Solution:**

## ABC is an isosceles triangle right angled at C. Prove that AB² = 2AC²

NCERT Class 10 Maths Solutions Chapter 6 Exercise 6.5 Question 4

**Summary:**

For a triangle ABC that is an isosceles triangle right angled at C, it is proved that AB^{2} = 2AC^{2}.

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