SOLUTION: solve. (x+18)(x-18)(x+17)>0

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Question 238020: solve. (x+18)(x-18)(x+17)>0
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
solve. (x+18)(x-18)(x+17)>0
x^3+17x^2-324x-5508>0
Use equal signs to start.
x=18, x=-18 x=-17 These numbers are inflection points at which the sign of y changes.
Now test when y>0
y=x^3+17x^2-324x-5508
x=-19 y=-74
x=-17.5 y=8.9
x=-16.5 y=-25.8
x=19 y=1332
.
Y>0 when -17>x>-18 and infinity>x>18
.
Ed
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graph%28500%2C500%2C-20%2C%2B20%2C-200%2C%2B200%2Cx%5E3%2B17x%5E2-324x-5508%29