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FACTORISING, which type do i use, when to find value of x and when to not??

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You're correct! Looking back through all my wokring i seemed to have made the stupid mistake of 3x x 8=28x instead of 24x ! :doh:

Thanks for your help everyone!

Original post by Notnek

You should get 0 = 14x^2 - 41x - 3.

Have another go and please post all your working if you get stuck. Also, for future questions please always post the original question and your full attempt.

Reply 21

simon0

Okay we have:

Ax^{2} + Bx + C = 0.

As others have stated, we have methods of finding values of x including:
- Quadratic equation,

- Completing the square.

However, as we have some large values we can try inspection.

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For inspection, we could try

(kx + l) (mx + n) \, = \, (km)x^{2} + (lm+kn)x + ln.

We need:

- ln = C

- lm +kn = B,

- km = A.

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For your equation: