document.write( "Question 1184214: A farmer is going to divide her 60 acre farm between two crops. Seed for crop A costs $30 per acre. Seed for crop B costs $15 per acre. The farmer can spend at most $1200 on seed.\r
\n" ); document.write( "\n" ); document.write( "If crop B brings in a profit of $80 per acre, and crop A brings in a profit of $120 per acre, how many acres of each crop should the farmer plant to maximize her profit?\r
\n" ); document.write( "\n" ); document.write( " acres of crop A
\n" ); document.write( " acres of crop B
\n" ); document.write( "

Algebra.Com's Answer #815167 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
x = number of acres for crop A.
\n" ); document.write( "y = number of acres for crop B.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "your objective function is equal to 120x + 80y.
\n" ); document.write( "this is the profit function that you want to maximize the value of.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "your constraint functions are:
\n" ); document.write( "x + y <= 60 (acres)
\n" ); document.write( "30x + 15y <= 1200 (money spent on seeds)
\n" ); document.write( "x >= 0, y >= 0 (must not be negative)\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "using the desmos.com calculator, you would graph the opposite of these inequalities.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "specifically, you would graph:
\n" ); document.write( "x + y >= 60
\n" ); document.write( "30x + 15y >= 1200
\n" ); document.write( "x <= 0, y <= 0\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the area on the graph that is not shaded is your region of feasibility.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the corner points of this region are where the maximum profit lies.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "all the constraints must be met at the corner point where the maximum profit lies.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the graph is shown below:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the maximum profit is at the point (x,y) = (20,40).\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "at this point, the profit is 120x + 80y = 5600.
\n" ); document.write( "the number of acres is x + y = 60.
\n" ); document.write( "the amount spent on seeds is 30x + 15y = 1200.
\n" ); document.write( "all values of x and y are greater than or equal to 0.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "your solution is that the farmer should plant 20 acres of crop A and 40 acres of crop B to maximize profits.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "here's a picture of what the graph shows.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "the graphing calculator can be found at https://www.desmos.com/calculator\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );