Answer:
r = 15
Step-by-step explanation:
I don't really have an explanation, I'm just good at quick math,
I'm sorry if you wanted an explanation, I would explain but I am really bad at explaining math.
Slope of AB = 1/3 and slope of BC = -3 so these 2 lines are perpendicular
The same is true for all the other adjjacent pairs of lines.
Oppoitse lines are also paralllel ( slope of AB = 1/3 and slope of DC = 1/3) and other pair are both of slope -3.
So Its C
Answer:
slope = 5/8
Step-by-step explanation:
use the slope formula to find the slope: 
