Question

In an isosceles right triangle, the length of the hypotenuse is $10\text{cm}$. Then the perimeter of the triangle is:

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

In $△ABC$,
By Pythagoras theorem,
$A{B}^2+B{C}^2=A{C}^2$
$x^2+x^2={10}^2$
$x^2=\frac{100}{2}=50$
$x=5\sqrt{2}\text{cm}$
The perimeter is $5\sqrt{2}+5\sqrt{2}+10=10(\sqrt{2}+1)\text{cm}$