Can someone help answer this?

in a right angled triangle, (height)^2 + (base)^2 = (hypotenuse)^2

here we have , height as X and base as X too , so; x^2 + x^2 = (9√2)^2

2(X)^2 = 162

x^2 = 162/2

X^2 = 81

X = √81 = 9

true

step-by-step explanation: