SOLUTION: What are the roots for this Polynomial Equation? X*3+6X*2+5X+30?

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Question 259596: What are the roots for this Polynomial Equation?
X*3+6X*2+5X+30?

Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
Here's the way to solve this.
X*3+6X*2+5X+30 Let's work on the first two:
X*3+6X*2 and rewrite this as: x^2(x+6)
Now let's work on the last two
5X+30 and rewrite this as: 5(x+6)
Notice we have in both parenthesis the same (x+6) so now we can rewrite the whole
polynomial as:
(x^2+5)(x+6)=0 (I see the original didn't have it equal to zero but should be)
Now we can solve for x
x^2+5=0 Subtract 5 from both sides to give us:
x^2=-5 Sq rooting both sides gives us a negative sq rt so we know that's not right.
x+6=0 Subtract 6 from both sides gives us:
x=-6 Plug this into the original equation and it works out.
RJ
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