x = number of acres of corn.
y = number of acres of soybeans.
make a table as shown below:
x y
corn soybeans
fertilizer gallons 7 3 <= 40,500
harvest hours .5 1 <= 5,250
profit 50 45 maximize
using the desmos.com calculator, graph the opposite of the constraints and then evaluate the objective function at the corner points of the feasible region.
the constraint functions are:
7x + 3y <= 40,500
.5x + y <= 5250
x,y >= 0
the objective function is:
profit = 50x + 45y
you are graphing the OPPOSITE of the constraint inequalities.
here's what the graph looks like:
maximum profit is at the point (4500,3000).
profit is 50*4500 + 45*3000 = 360,000
gallons of fertilizer used are 4500*7 + 3000*3 = 40,500 <= 40,500
hours of labor = 4500*.5 + 3000*1 = 5250 <= 5250
looks like all the available resources were used when the maximum profit was attained.