SOLUTION: 2x2 + 9x + 4 < 0 I could really use some help with this one

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Question 335605: 2x2 + 9x + 4 < 0
I could really use some help with this one
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
+2x%5E2+%2B+9x+%2B+4+%3C+0
%282x%2B1%29%28x%2B4%29%3C0
Break up the number line into 3 regions.
Region 1:(-infinity,-4)
Region 2:(-4,-1%2F2)
Region 3:(-1%2F2,-infinity)
Choose a point in each region (not an endpoint) and test the inequality.
If the point satisifes the inequality, that region is part of the solution region.
Region 1: x=-5
%282x%2B1%29%28x%2B4%29%3C0
%282%28-5%29%2B1%29%28-5%2B4%29%3C0
%28-9%29%28-1%29%3C0
9%3C0
False, this region is not part of the solution.
.
.
.
Region 2: x=-3
%282x%2B1%29%28x%2B4%29%3C0
%282%28-3%29%2B1%29%28-3%2B4%29%3C0
%28-5%29%281%29%3C0
-5%3C0
True, this region is part of the solution.
.
.
.
Region 3: x=0
%282x%2B1%29%28x%2B4%29%3C0
%281%29%284%29%3C0
4%3C0
False, this region is not part of the solution.
.
.
.
The solution region is (-4,-1%2F2)
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.
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Graphical verification by graphing 2x%5E2%2B9x%2B4 and looking for the region where the function is less than zero (below the x-axis)