how do i find the length x of a right triangle,when one side is x+48(hypotenuse) and the other is 72.?????????

(x+48)^2=x^2+72^2

Or x^2+2304+96x=x^2+5184
Or 96x=5184-2304=2880
Or x=30
Check: (30+48)^2=72^2+30^2
Or 6084=5184+900 ok.