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Factor 3x^2-20x-7.
I need the steps of factoring it out please, don't just put the question into a calculator and give me an answer. I want to get how to do it.

Respuesta :

caylus

Hi,

Without discriminant:

[tex] 3x^2-20x-7\\\\
=3(x^2-\dfrac{2*10}{3} )-7\\\\
=3(x^2-\dfrac{2*10}{3}+\dfrac{100}{9} )-\dfrac{100}{3}-7\\\\
=3(x-\dfrac{10}{3})^2-\dfrac{121}{3}\\\\
=\sqrt{3}[(x-\dfrac{10}{3})+\dfrac{11}{3}]*\sqrt{3}[(x-\dfrac{10}{3})-\dfrac{11}{3}]\\\\
=3(x+\frac{1}{3})(x-\dfrac{21}{3})\\\\
=(3x+1)(x-7)
[/tex]

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