graph the following and find the point of intersection
2x+y=-4
y+2x=3
Those are two parallel lines with different y intercepts. They never intersect and there is no solution.
2 x + y = -4
and
2 x + y = 3
each has slope = -2
2x+y=-4
y+2x=3
2 x + y = -4
and
2 x + y = 3
each has slope = -2