Answer:
W = 8.5 units; L = 30.5 units
Step-by-step explanation:
The formula for the perimeter of a rectangle is P = 2L and 2W, where L and W represent the length and the width respectively. Here, L = 3W + 5. Adapting the formula P = 2L and 2W, we get:
78 = 2L + 2W = 2(3W + 5) + 2W, or
6W + 10 + 2W = 78, or
8W = 68, or W = 68/8 = 8.5 units
If W = 8.5 units, then L = 3(8.5 units) + 5 units = 30.5 units