Answer:
W = 8.2 cm
Explanation:
The perimeter formula is P = 2W + 2L and here the perimeter is 65.6 cm.
Thus, 65.6 cm = 2W + 2L. Substituting 3W for L, we get
65.6 cm = 2W + 2(3W) = 8W.
Solving for W by dividing both sides by 8, we get W = 65.6 cm / 8, or
W = 8.2 cm