let
x------------------- >acres of corn
y------------------- >acres of soybeans
we have that
x>=40
y>=50
and
x+y <= 200------------------ > y <= 200-x
using a graph tool
see the solution in the attached figure
the solution is the triangle formed with the point ABC
A(40,50) -------- > minimum acres of corn (40) and minimum acres of soybeans (50)
B(40,160) -------> minimum acres of corn (40) and maximum acres of soybeans (160)
C(150,50) ------ > maximum acres of corn (150) and minimum acres of soybeans (50)
List two possible combinations
see the graph
point (100,100)---> acres of corn 100 and acres of soybeans 100
point (50,150)---> acres of corn 50 and acres of soybeans 150