Posted by **chirag** on Tuesday, February 12, 2013 at 9:41am.

x is a number such that x2+3x+9=0. What is the value of x3?

- maths -
**Steve**, Tuesday, February 12, 2013 at 10:15am
since (x-3)(x^2+3x+9) = x^3 - 3^3

x^3 - 3^3 = 0

x^3 = 27

- WoW at Steve - maths -
**Reiny**, Tuesday, February 12, 2013 at 11:52am
What a great way to do this question.

Did you see the round-about way I used ??

http://www.jiskha.com/display.cgi?id=1360597831

I was even thinking of using DeMoivre's theorem.

- WoW at Reiny - maths -
**Steve**, Tuesday, February 12, 2013 at 4:07pm
I was going to show an alternative direct solution, but when I saw where it was headed, I blew it off.

Can't believe you

(a) slogged through it all

(b) got it right!

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