You can put this solution on YOUR website! 6x + 6y =5
6x - 6y =3
Are they parallel, perpendicular or neither?
y=-x+5/6 (red line)
y=x-1/2 (green line).
Because the slopes (m) are negative recipricals then these 2 lines are perpendicular as shown by the following graph.
(graph 300x300 pixels, x from -10 to 10, y from -10 to 10, of TWO functions -x +5/6 and x -1/2).