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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE General & Further Mathematics => Topic started by: daveskee on October 31, 2010, 05:32:39 pm

Title: please help
Post by: daveskee on October 31, 2010, 05:32:39 pm

i'm having trouble knowing which sides to shade for constraints (region required).
can someone please explain?

Title: Re: please help
Post by: jasoN- on October 31, 2010, 05:35:24 pm

if it is, for example, y < 5-x;
draw up the line y=5-x
as there is a 'less than' sign, imagine pushing down on that line, values under it are in the feasible region.
A greater than sign means everything above that line
If they give you an equation such as 20x + 30y > 400, rearrange that to make y the subject, then repeat the same method as above

Still not convinced? after you shade in the feasible region, test a point (coordinate) that's inside the region you shaded into all the inequalities. If it the point satisfies all, then you are correct