#1. x(2400-2x)
#2. x(1800-6x)/2
Both of these are just parabolas, where the maximum area occurs at the vertex of the parabola.
Recall that for y = ax^2+bx+c, the vertex is at x = -b/2a
Word Problems:
1. A farmer has 2400 feet of fencing and wants to fence off a rectangular field that borders a straight river. If he needs no fence along the river, what are the dimensions of the field that he can fence with the largest area? Find the area of the field.
2. If 1800 feet of fencing is available to build five adjacent pens, express the total area of the pens in terms of x. What value of x will maximize the total area?
1 answer