If you have difficulty in understanding your textbook, your friends in your class, and your teachers, then I suggest that you seriously consider going to a private tutor, even though it may cost some money. Websites such this one is not indtended to be substitute for a good Math teacher or a good tutor.
Your question about Linear programming is rather unusual. Do you really expect somebody to spend hours with you on this Website? You should be realistic and apply yourself to your studies. Good luck to you.
Mmmmm.....that's too broad of a topic to answer such a question on a forum like this one, Paypay.
Here's some help from PurpleMath : http://www.purplemath.com/modules/linprog3.htm
Please realize that the main pre-requisite for this topic is being able to plot inequalities on a graph, finding the "corner" points, and then, putting the results back into an "objective function" to see which of these points lead to a "min" or a "max"......thus, there are several Algebra skills involved!!!