Question 274231
3x-y=2x-7
-y=2x-3x-7
-y=-x-7
y=x+7 (red line)
2x+5=2y-9
-2y=-2x-9-5
-2y=-2x-14
y=-2x-2-14/-2
y=x+7 (green line)
These lines are the same.
{{{ graph( 300, 200, -8, 5, -10, 10, x +7, x +7) }}} (graph 300x200 pixels, x from -8 to 5, y from -10 to 10, of TWO functions x +7 and x +7). 
Solutions:
(-7,0)(0,7)
(2,9)(9,16)
(-4,3)(3,10)  
(5,12)(12,19)