<u>Answer:</u>
5.65 cm
<u>Step-by-step explanation:</u>
We are given that the length of each leg of an isosceles right triangle is 4 cm and we are to find the length of the hypotenuse.
For this, we will use the Pythagoras Theorem:

where
is the hypotenuse.



Therefore, the length of the hypotenuse is 5.65 cm.
Here is the set up:
(1/4)/2 = (9/4)/y
Solve for y.
That is quite simply and astoundingly:
3.482 x 10^9