Question

х-у=1
Х^2-у^2=7
Решить систему

Answer 1

x=1+y→
(1+y)^2-y^2=7
1+2y+y^2-y^2-7=0
1+2y-7=0
2y-6=0
2y=6
y=3

Answer 2

x=1+3=4