F(x) =4x -2
xy= 4
y = 4x -2
x-6 +2y =0
F(x) = (x+2)/6
F(x) = 5- 3x
1/x + y = 0
F(x) = -1/x
6y = x +2
F(x) = 4/x
F(x) = (-x +6)/2
3x + y =5
