Question

2x + y =5
2x - y = 1

Answer 1

{2x+y=5
{2x-y=1
4x=6
x=6/4 (÷2)
x=3/2
2x-y=1
2.3/2-y=1
3-y=1
-y=1-3
-y=-2.(-1)
y=2
S={3/2, 2}