SOLUTION: Solve the inequality. x^2+2x_>35. _> is greater than or eqaul to

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Question 336875: Solve the inequality. x^2+2x_>35. _> is greater than or eqaul to
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B2x%3E=35
x%5E2%2B2x-35%3E=0
%28x%2B7%29%28x-5%29%3E=0
Break up the number line into three regions.
Region 1: (-infinity,-7)
Region 2: (-7,7)
Region 3: (5,infinity)
Choose a point in each region (not an endpoint) and test the inequality.
If the inequality is satisfied, that region is part of the solution.
Region 1:x=-8
%28x%2B7%29%28x-5%29%3E=0
%28-8%2B7%29%28-8-5%29%3E=0
-1%28-13%29%3E=0
13%3E=0
True, this region is part of the solution region.
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Region 2:x=0
%28x%2B7%29%28x-5%29%3E=0
%280%2B7%29%280-5%29%3E=0
7%28-5%29%3E=0
-35%3E=0
False, this region is not part of the solution region.
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Region 3:x=6
%28x%2B7%29%28x-5%29%3E=0
%286%2B7%29%286-5%29%3E=0
13%281%29%3E=0
13%3E=0
True, this region is part of the solution region.
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Solution Region:(-infinity,-7) U (5,infinity)
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Graphical verification:
x%5E2%2B2x-35%3E=0
Look for the region where the function is above the x-axis.
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