Question

Решить систему уравнений
X^2-y^2=72
X+y=9

Answer 1

x = 9 - y
(9 - y)^2 - y^2 = 72
81 - 18y + y^2 - y^2 = 72
-18y = 72 - 81
18y = 9
y = 1/2 = 0,5
x = 8,5