Answer: 13 feet
Step-by-step explanation: You are given that the perimeter, P, of the rectangle is 42 meters (i.e., P = 42). Also, the length, L, of the rectangle is 3 meters less than 2 times the width, W (i.e., L = 2W - 3).
Recall that the perimeter, P, of a rectangle is given by the following formula:
P = 2W + 2L
Substituting 2W - 3 for L, we arrive at the following:
P = 2W + 2(2W - 3)
P = 2W + 2·2W + 2·-3
P = 2W + 4W - 6
P = 6W - 6
Since we were given that P = 42, then
42 = 6W - 6
42 + 6 = 6W - 6 + 6
48 = 6W
48/6 = 6W/6
8 = W
Therefore, the width of the rectangle is 8 meters. Use this value to solve for the length:
L = 2W - 3
L = 2·8 - 3
L = 16 - 3
L = 13
