Question 144591: Solve. (x+4)(x-5)(x+3)>0
What is the solution set? {x }
Thank you I really need help with this!!!
Answer by nabla(475)   (Show Source):
You can put this solution on YOUR website! What I would do first here is make note of the zeros (-4,5,and -3). Next, I would find out what happens to the sign of values in between and outside those zeros. This will give you where the left side will be positive or negative. Note, however, that none of the zeros are valid as part of the solution set because they make the left side 0.
So, make a chart of values as I detailed above. The exact numbers chosen don't matter.
-5, -3.5, 0, 6
gives left-side signed values of
-, +, -, +
So from this we surmise that (x+4)(x-5)(x+3)>0 when x is between -4 and -3, and when greater than 5.
In interval notation we will have: (-4,-3)U(5, )
I'll check via graphing:
|
|
|
