if you know the rules, you don't actually have to graph these to check if they're perpendicular, parallel, or neither.
parallel slopes are the same
perpendicular slopes are the opposite reciprocals
"neither" slopes fall into neither category
you should still follow directions and graph them if your teacher expects it, but with that knowledge:
13. y = 4x+7 and y = (-1/4)x-3
the slopes here, 4 and -1/4, are opposite reciprocals, so these lines are perpendicular
14. y = 3x-4 and y = 3x+1
the slopes here, 3 and 3, are the same, so these lines are parallel
15. y = x+5 and y = -5x-1
the slopes here, 1 and -5, have no relation in this case, so these lines are neither
