Question 238139
2x+y=3 
y=-2x+3 (red line)
3y=x-12
y=x/3-12/3
y=x/3-4 (green line)
{{{ graph( 300, 200, -6, 5, -10, 10, -2x +3, x/3 -4) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions -2x +3 and x/3 -4). 
Intersection: (3,-3)