Hello,
Let's assume top left corner: A
top right corner : B
Bottom right corner: C
Bottom left corner :D
M= middle of [CD]
ABM is a triangle rectangular isocel:
(3√2)²+(3√2)²=y²
==>y²=2*9*2
==>y²=36
==>y=6
The triangle BCM is rectangular with MB=3√2, MC=y/2=3
x²+3²=(3√2)²
==>x²=9*2-9
==>x²=9
==>x=3
