SOLUTION: x^3 + 6x^2 + 13x = 0 Find the solution of the equation

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Question 649691: x^3 + 6x^2 + 13x = 0
Find the solution of the equation
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
You can factor out an x first of all.
x%5E3+%2B+6x%5E2+%2B+13x++=+x%28x%5E2%2B6x%2B13%29
So x =0 is one.
Now we have a good old quadratic.
13 is prime, so we can't factor this into any integer solution.
Use the quadratic formula
x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F2a
x+=+%28-6+%2B-sqrt%2836+-+52%29%29%2F2
x+=+%28-6+%2B-+sqrt%28-16%29%29%2F2
+x+=+%28-6+%2B-+4i%29%2F2
+x+=+-3+%2B-+2i and x=0
If you have not learned imaginary numbers, just say x=0 is the only real solution.
Hope this helps!
-Devin
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