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- Nov 7th 2013, 08:23 PMvegasgunnerplz help and include answer plz
- Nov 7th 2013, 08:47 PMProve ItRe: plz help and include answer plz
We don't give full solutions here. When you show that you have made an attempt and show exactly where you are stuck, then we can help you further.

- Nov 8th 2013, 12:55 AMpsimianRe: plz help and include answer plz
Here's some things to get you started:

1) This problem can be re-written as a^2 + a = 12 by substituting some bits for a (I'll let you figure that out).

2) Second order equations (of which this is one) have at most 2 solutions.

3) solve the equation in part (1)

4) express a in terms of x

5) the larger of the two solutions for x is your answer

note: it is possible for second order equations (quadratics) to have only a single solution.