SOLUTION: I seem to be having some trouble with inequalities. Its a really simple problem but I keep finding no solution I could really use some help. x2 - 9 > 0 A x < -3 or x > 3 B

Algebra ->  Inequalities -> SOLUTION: I seem to be having some trouble with inequalities. Its a really simple problem but I keep finding no solution I could really use some help. x2 - 9 > 0 A x < -3 or x > 3 B       Log On


   

Question 330853: I seem to be having some trouble with inequalities.
Its a really simple problem but I keep finding no solution I could really use some help.
x2 - 9 > 0
A x < -3 or x > 3
B -3 < x < 3
C x < -3 or x > 2
D-3 < x < 2
E -2 < x < 4.5
F for all x
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E2+-+9+%3E+0
%28x-3%29%28x%2B3%29%3E0
Break up the number line into 3 regions.
Region 1:(-infinity,-3)
Region 2:(-3,3)
Region 3:(3,infinity)
Pick a point in each region (not an endpoint).
Test the inequality.
If the inequality is satisfied, the region is part of the solution.
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.
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Region 1: x=-4
%28x-3%29%28x%2B3%29%3E0
%28-4-3%29%28-4%2B3%29%3E0
%28-7%29%28-1%29%3E0
7%3E0
True, this region is part of the solution.
.
.
.
Region 2: x=0
%28x-3%29%28x%2B3%29%3E0
%28-3%29%283%29%3E0
-9%3E0
False, this region is not part of the solution.
.
.
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Region 3: x=4
%28x-3%29%28x%2B3%29%3E0
%284-3%29%284%2B3%29%3E0
%281%29%287%29%3E0
7%3E0
True, this region is part of the solution.
.
.
.
(-infinity,-3)U(3,infinity)
.
.
.
Graphically, look for the regions where the function is greater than zero (above the x-axis).
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