Remember, isosceles means that two of the legs are equal in length. Since the hypotenuse of a right triangle is always longer than the other two sides, this means that the other two are equal.

This, in turn, signifies that this is a traditional 45-45-90 triangle. Remember that with these triangles, the hypotenuse is equal to one of the legs multiplied by root 2.

If the leg length is x, we have x + x + root(2)*x = 16 + 16*root(2). Some quick algebra shows that x is equal to 8*root(2), which makes the hypotenuse equal to (8*root(2))*root(2), or 16.

solving the algebraic part was cofusing for me hwo did u solve it

cuz this is the farthest i can go

x+x+x root 2 = 16+ 16 root 2
so
2x+xroot2= 16 +16root 2

x(2+root2) = 16(1+ root 2)

x= 16 (1+ root2) /2 +root 2)

im a bit confused now??

Yeah, it's just algebra. I think you're going about it the wrong way.
(From now on, let's just call root(2) r2.)

x + x + r2x = 16 + 16r2

(2 + r2)x = 16 + 16r2

x = (16 + 16r2) / (2 + r2)

x = 8r2 (2 + r2) / (2 + r2)

x = 8r2