Please help i don’t understand

Explanation:

since this triangle is a right-angled triangle and one its angles equals 45° then it's an isosceles right triangle which means that the side opposite 45° (the side to the left) is equal to 13 too.

so according to pythagoras theorem c = √(a²+b²)

x =√(13²+13²)

x = √(169+169)

x = √338

x ≈ 18.38

note: in the question it's mentioned to find y! and I believe it is just an error! it's about to find x and that's more resonable!

do you have the measurements?