Answer:
Let x represents acres of corn to be planted.
Let y represents acres of soybeans to be planted.
A farmer has a 320 acre farm on which she plants two crops. We get;

Other equations as per scenario becomes:




We have to find the profit. So let the profit be p. We can give this by:

When we graph these functions, we get the following.
(0,200) putting these in
we get profit as $1800
(140,130) , we get $20,100
(192,0) we get $11520
In the graph, we have points (240,180) but this is not possible as
so, we have (140,130) to get the maximum profit.