Surviving College Algebra
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Graphing Systems of Inequalities

 

Graphing systems of inequalities is like graphing systems of equations. The main difference being that the intersection of the different graphs can be very large as opposed to a single point in equations. In other words, the solution to a system of inequalities is an area of the graph that satisfies all the conditions of the system.

 

Example

Graph the system

y > x2 + 2

y > 2 x + 4

 

Graph the first inequality.

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On the same graph, graph the next inequality, y ≤ 2 x + 4.

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The area that is shaded in twice is the area that meets both conditions.

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Answer!

 

 

 

 

 

 

Example

Graph the following system

 

y –x 2

x -3

x 2

y ≤ 5

 

Graph all of the inequalities on the same graph. The area that matches all of these inequalities is the solution.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Answer!

Note- All the points that are shaded in the graph are solutions. The points ( -2, 3), ( -1, 2), and (3, 4) are all in the shaded area and therefore are possible solutions to the system.