Answer: Length: 21 cm Width: 7 cm
Step-by-step explanation:So, two of the sides are 3 units long, and two of the sides are 1 unit long. The total number of units in the perimeter of the rectangle is 8.
56cm / 8units = 7cm/unit
So, the length of the rectangle is 7cm/unit x 3 units, or 21 cm.
The width of the rectangle 1/3 of the length, or 7cm.
Length: 21 cm
Width: 7 cm