which lines are parallel y=6;y=6x+5;y=6x-7;y=-8

Answer 1

y=6x+5 and y=6x-7

These to lines are parallel because they have the same slope. y=6 and y=-8 doesn't even have a slope so they are not related.

If it was y=6x+5 and y=-1/6x-7, then the two equations would be perpendicular because they are opposite reciprocals.

Answer 2

y=6;y=6x+5;y=6x-7;y=-8