Answer:
E.
Step-by-step explanation:
we know the diagonal of the square : 2
as you can see in the picture, there is a right-angled triangle with the baseline of Hypotenuse being the diagonal, and 2 times s being the 2 sides.
that means we can use Pythagoras to calculate s :
2² = s² + s²
4 = 2s²
2 = s²
s = sqrt(2)
