Question 170643
X=4y+8 
4y=x-8
y=x/4-8/4
y=x/4-2 (red line)
2x-8y=-3
-8y=-2x-3
y=-2x/-8-3/-8
y=x/4+3/8 (green line)
{{{ graph( 300, 200, -6, 5, -10, 10, x/4 -2, x/4 +3/8) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions x/4 -2 and x/4 +3/8). 
No unique solution for x or y as these two lines are parallel.