Chapter 6: Linear Programming – Working out value when lines cross

Hi,

I have just gone through chapter 6 and was wondering when it comes to working out the value when the lines cross on the graph.

In the lecture the materials (2S + 4E = 80) & labour (5S + 6E = 180), Materials were multiplied by 2.5 giving 5S + 10E = 200. The rest was then worked out from this equation.

My question is, do you always multiply by 2.5? As in the lecture I heard mentioned that you can also multiply by 1.5 and this would come to the same answer.

Any help would be appreciated

Thanks

Oli