Systems of Inequalities: y > -x + 1, y > (5/2)x - 3

[sissylokey]

We have had a substitute teacher for about two weeks now, because my teacher is out with her newborn baby, and I'm feeling a bit lost. We just started "systems of inequlities", and I'm not really catching on.

I have this problem here, and it is driving me bonkers because I have tried so many diffrent ways to do it, and yet it never comes out right. The question is:

Determine the solution to the following system of inequalities:

. . .y > -x + 1
. . .y > (5/2)x - 3

I've been looking it up and I know I'm supposed to graph this, but what I don't understand is how you solve for everything. I mean, what are you supposed to substitute? Are you allowed to substitue for with fractions since there is a fraction, or do you just use regular numbers?

I am so lost. Thank you for any help or advise!
:x

 

[stapel]

I'm not sure what you mean by "substituting number", or what fractions would have to do with anything...?

Just graph "y = -x + 1" and "y = (5/2)x - 3" in the usual manner, except for drawing the lines as dashed lines, since these are not "or equals" inequalities. Then shade the appropriate side of each line.

The "solution" is the overlap of the two shadings.

Eliz.

 

[sissylokey]

Cool, that helped. Thanks!