Answer:
The lines are not parallel nor perpendicular.
Explanation:
Since the first equation is shown in a slope form, we also want the second equation to be in slope form. Subtract x from x+3y=21 on both sides to get this equation 3y = -x + 21. You would need to divide 3 on both sides for this equation y = -1/3x+7 in which 21 is divisible by 3. Due to the two slopes going in opposite directions, it is safe to say that they are intersecting but a perpendicular line has to be a 90-degree angle, and because when you put it on the calculator, the second slope is more straight than the first angle making it not parallel or perpendicular.