These lines are parallel because the slopes are the same that's the number with the X . They never touch
Y= -1/2x+8 Y= 2x+ 8
If the X has opposite signs and they are reciprocal of each other like -1/2 and 2/1 they are perpendicular. They cross (intersect) each other and make a 90 degree angle. Perfect L shape when they cross each other they are perpendicular
