Answer:
n must be 3
Step-by-step explanation:
The formula for the perimeter of a rectangle of length L and width W is
P = 2L + 2W. Substituting (1/2)(n - 6) for L and 2n + 5 for W, we get:
P = 60 = n - 6 + 4n + 10, or:
60 = 5n + 4, or:
15 = 5n
Then n must be 3.
