Respuesta :
Always
If you have a straight horizontal line and need to put two perpendicular lines on it, they make a 90 degree angle at each angle, therefore both lines are parallel
___l____l___ (quick visual)
Always
If you have a straight horizontal line and need to put two perpendicular lines on it, they make a 90 degree angle at each angle, therefore both lines are parallel
___l____l___ (quick visual)