# Thread: Linear programming with upper limit

1. ## Linear programming with upper limit

I have the following linear programming model:

$p = 10x+15y$

Constraints:
$1x+2y \le 600$
$0.125x+0.5y \le 100$
$0.05x+\frac{1}{3}y \le 60$
$0 \le x\le 500$

The constraint I'm struggling with is the last one (about x's maximum value).

I've been taught to solve them by plotting the points. When you plot the points, the x value is always greater than 500 (in this case, 600,800 and 1200).

What is the appropriate course of action here? Do I just assume $x$ is 500, or do I need to do something else?

2. ## Re: Linear programming with upper limit

've been taught to solve them by plotting the points

You must modify your code so that the last restriction is included in the results

3. ## Re: Linear programming with upper limit

Having looked at an online calculator, it appears I just continue as normal (plotting the points) and simply put it out of range when I'm finding the corners.

Here's a link to the calculator, in case anyone else is looking in the future.
PHPSimplex: Graphical method