You can't. It's an equation with two variables. It's a graph of a line. The best you can do with it is draw a graph, put a dot at (0,4) and another dot at (1,1) and draw a line through the dots.
-y + y equals 0.
For y - 2y - 3y equals 0, y equals 0.
y - 3 = 0 y = 3
For x-2x= 3x-43x+1 x-2x= -x and 3x-43x+1 = -40x+1 so -x= -40x+1 subtract -x from both sides 0= -39x +1 -1 = -39x so 1=39x so x=1/39
y = -6
-y + y equals 0.
For y - 2y - 3y equals 0, y equals 0.
b = y - mx.
y= -2x
y - 3 = 0 y = 3
For x-2x= 3x-43x+1 x-2x= -x and 3x-43x+1 = -40x+1 so -x= -40x+1 subtract -x from both sides 0= -39x +1 -1 = -39x so 1=39x so x=1/39
y=x+4
y = -6
-3
y=5-x
16
y = mx + b