Question 107522
x-2y=8 or -2y=-x+8 or y=-x/-2+8/-2 or y=x/2-4 (red line)
3x-2y=12 or -2y=-3x+12 or y=-3x/-2+12/-2 or y=3x/2-6 (green line)
{{{ graph( 300, 200, -6, 5, -10, 10, y = x/2 -4, y = 3x/2 -6) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = x/2 -4 and y = 3x/2 -6). 
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3x-6y=9 or -6y=-3x+9 or y=-3x/-6+9/-6 or y=x/2-3/2 (red line)
x-2y=3 or -2y=-x+3 or y=-x/-2+3/-2 or y=x/2-3/2 (green line)
these 2 equations are identical therefore there is no unique solution or no intersect.
{{{ graph( 300, 200, -6, 5, -10, 10, y = x/2 -3/2, y = x/2 -3/2) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = x/2 -3/2 and y = x/2 -3/2).