Question

Beth has 4900 feet of fencing available to enclose a rectangular field. one side of the field lies along a river, so only three sides require fencing. express the area a of the rectangle as a function of x, where x is the length of the side parallel to the river.

Answer 1

Perimeter (P) = 2L + x

4900 = 2L + x ⇒ 4900 - x = 2L ⇒
`(4900 - x)/(2)` = L

Area (A) = L · x

A = (
`(4900 - x)/(2)`) (x)

=
`(4900x - x^2)/(2)`