SOLUTION: This really has me confused!!! (x+5)(x-20)(x+3) > 0 Thank you for all your help!!!

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Question 250978: This really has me confused!!!
(x+5)(x-20)(x+3) > 0
Thank you for all your help!!!

Found 2 solutions by vksarvepalli, Fombitz:
Answer by vksarvepalli(154) About Me  (Show Source):
You can put this solution on YOUR website!
(x+5)(x-20)(x+3) > 0
for this to happen all the three terms must be positive or two positive and one negative ,considering these cases we get the solution set as
x belongs to (-5,-3)u(20,infinity)
you will get a very clear picture if you draw the number line and consider the points -5, -3 and 20.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Break up the number line into 4 regions.
+x%3C-5
-5%3Cx%3C-3
-3%3Cx%3C20
x%3E20
Pick a number in each region and test the inequality.
First region: +x=-10
%28-10%2B5%29%28-10-20%29%28-10%2B3%29%3E0
%28-5%29%28-30%29%28-7%29%3E0
-1050%3E0
False, not a valid region.
.
.
Second region: +x=-4
%28-4%2B5%29%28-4-20%29%28-4%2B3%29%3E0
%281%29%28-24%29%28-1%29%3E0
24%3E0
True, a valid region.
.
.
Third region: +x=0
%285%29%28-20%29%283%29%3E0
-300%3E0
False, not a valid region.
.
.
Fourth region: +x=30
%2830%2B5%29%2830-20%29%2830%2B3%29%3E0
%2835%29%2810%29%2833%29%3E0
11550%3E0+
True, a valid region.
x=(-5,-3)U(20,infinity)