SOLUTION: The function below can be used to model the area of a rectangle in square inches, A, if the rectangle has a perimeter of 72 inches and a width of W inches. A= 36w- w^2 pleas

Algebra ->  Rectangles -> SOLUTION: The function below can be used to model the area of a rectangle in square inches, A, if the rectangle has a perimeter of 72 inches and a width of W inches. A= 36w- w^2 pleas      Log On


   

Question 981170: The function below can be used to model the area of a rectangle in square inches, A, if the
rectangle has a perimeter of 72 inches and a width of W inches.
A= 36w- w^2
please describe the domain of the function:
0 < N < ?what number
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Two things to deal with:
-w%5E2%2B36w%3E0 and 2L%2B2w=72.

Also knowing that w is width, you can find length information.
A=w%28-w%2B36%29.
This means, L=36-w. Only positive values for L and w are allowed, so this means at least, that w%3C36.

The roots for area A=-w%5E2%2B36=-w%28w-36%29 are 0 and 36; and A is a parabola which has a maximum and opens downward.

highlight%280%3Cw%3C36%29