Question

Срочноооооо!!!!!!!!!!!!!!!1

Answer 1

x=9-y. (9-y)^2-y^2=72
81-18y+y^2-y^2=72
81-18y=72, -18y=-9,
y=0.5, x=9-0.5, x=8.5
проверяем
8.5^2-0.5^2=72
72.25-0.25=72
8.5+0.5=9
9=9