Question

Решите пожалуйста дам 40 балов

Answer 1

x+y=4
x-y=5

x=4-y
(4-y)-y=5

x=4-y
4+y^2=5

x=4-y
y^2=5-4

x=4-1
y=1

x=4-1
y=1

x=3
y=1