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INEQUALITIES - CHANGE SIGNS, GRAPHING

When solving inequalities, treat like an ordinary algebra problem, then worry about how to graph it. 
 
Don't forget to change signs if you have to divide or multiply by a negative number (such as -5 > -x > -15, which then becomes 5 < x < 15, in this equation X is between 5 and 15, open ended circles at those points (5 and 15), solid line inbetween. 
 
Example:
 
2x + 3 > y
 
or if it helps to look at it with the Y first:
 
y < 2x + 3
 
1)  Plug in values for X to obtain values HIGHER than Y
 
2) (0, <3) - NOTE, at the y < 3, put an open circle at the 3 and put a vertical line below since ALL numbers below THREE satisfy the equation.
 
3) (1, <5), again, at X = 1, an open circle at the 5 and vertical line below. 
 
4)  Connect the points for the line using dotted lines (because Y does NOT equal 3 or 5), A SOLID LINE REPRESENTS "EQUAL TO". 
 
5)  Graph will be a dotted line with all values underneath the "line" included. 
 

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