If the sides of a right triangle are x, x + 1 and x – 1, then the hypotenuse :

From given figure , we have
Let, (x + 1) be the hypotenuse and perpendicular = x - 1 , base = x.
By pythagoras theorem ,
∴ (x + 1)² = x² + (x + 1)² ⇒ x = 4
∴ Hypotenuse = 4 + 1 = 5