Question

Please Help me! What is the value of y?

Answer 1

See the picture with letters attached to better understand the problem

we know that
in the right triangle ABC
AB=BC----------> by angle 45°
AC²=AB²+BC²-----> AC²=(√2)²+(√2)²----> AC²=4-----> AC=2

in the right triangle ACD
tan 60°=y/AC--------> y=AC*tan 60°-----> y=4*tan 60°----> y=4√3

the answer is
y=4√3