SOLUTION: Solve the rational inequality. State and graph the solution set. Can someone help? x/x+2>-1

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Question 23382: Solve the rational inequality. State and graph the solution set. Can someone help?
x/x+2>-1

Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
I'm assuming that you mean x%2F%28x%2B2%29+%3E-1.

If so, then I would begin by setting the inequality to zero. DO NOT MULTIPLY BOTH SIDES OF THE INEQUALITY BY (X+2)!!
x%2F%28x%2B2%29+%2B1%3E0.

Next, find a common denominator, which is x+2:
%28x%2F%28x%2B2%29%29%2B1%2A%28%28x%2B2%29%2F%28x%2B2%29%29+%3E0
%28x+%2B+x%2B2%29%2F%28x%2B2%29+%3E0
%28+2x+%2B+2%29%2F%28x%2B2%29+%3E0+

Now, you have two choices for method of solving the inequality. You can use some algebra explanations to solve it, or you can use a graphing calculator (or the algebra.com calculator!!). I will choose the latter method. You need to graph y=+%282x%2B2%29%2F%28x%2B2%29+. Before drawing the graph, notice that there is one place that the numerator equals zero, and that is at x= -1. There is one value of x that would make the denominator zero, which is NOT allowed, and that would be x= -2. This tells me that there is a ROOT at x = -1 and an ASYMPTOTE at x= -2. Now, draw the graph with this in mind:
graph%28500%2C500%2C+-10%2C10%2C-10%2C10%2C+%282x%2B2%29%2F%28x%2B2%29+%29

Now, since the problem is to solve %28+2x+%2B+2%29%2F%28x%2B2%29+%3E0+, which is solving a problem that is "GREATER THAN", you need to find all values of x for which the graph is ABOVE the x-axis. And do NOT include the endpoints.
Notice that the graph is above the x-axis from -infinity to -2, and also from -1 to infinity.
This means that the solution is x<-2 or x>1.
In interval notation this will be:(-inf, -2) U (-1, inf).

R^2 at SCC