The perimeter of a rectangle is 310 meters. Express the area A(L) as a function of the length L, and state the domain of this function.
The perimeter of a rectangle is equal to twice the sum of the length and width.
P = 2(L +W)
310 = 2(L+W)
155 = L +W
155- L = W
The area of a rectangle is equal to the product of the length and width.
A = LW
A = L(155-l)m2
The domain of the function is the set of all real numbers L such that
0 < L < 155.