Please...I really need help with this story problem. HELP!

Marks pet needs to eat at least 18 grams of fiber but less than 25 grams of protein each day. Mark gives his dog Food A and Food B throughout the day. Food A has 2 grams of fiber and 3 grams of protein in each serving. Food B has 4 grams of fiber and 1 gram of protein for each serving.
a. Write a system of inequalities that determine the maximum and minimum amount of each food Mark can give his pet each day. Will the amount of Food A or B ever be negative? Please account for this in your system of inequalities.
b. Give three solutions that would solve Marks pet needs. Show that each solution works.

2 answers

2A+4B>18
3A+1B < 25
A>0
B>0

(A,B) = (1,5) …2(1)+4(5)>18 and 3(1)+1(5) < 25
(A,B) = (2,5) …2(2)+4(5)>18 and 3(2)+1(5) < 25
(A,B) = (3,5) …2(3)+4(5)>18 and 3(3)+1(5) < 25
If you copy and paste this solution, you will earn a 0 for plagiarism. Do your own work. Solve it a different way.