Answer:
d. 40 units
Step-by-step explanation:
The length of the horizontal side of this rectangle on the line y=20 is the difference of the x-coordinates, 12 and 20, so is 8. The length of the vertical side on the line x=20 is the difference of the y-coordinates, 20 and 8, so is 12.
Two sides are of length 8 and two are of length 12. The perimeter is the sum of the side lengths, so is ...
P = 2·8 +2·12 = 40 . . . units
