Answer:
Length = 25 km
Explanation:
Let L = length, W = width
L = 3W - 2
Perimeter of a rectangle given L and W is 2(L + W) and is given as 68
==> 2(L + W) = 68
==> So L + W = 68/2 = 34
Since L = 3W -2
L + W = 3W -2 + W = 4W - 2
L + W = 4W - 2 = 34
Solve 4W - 2 = 34:
4W = 34+ 2 = 36
W = 36/4 = 9
L = 3 x 9- 2 = 25