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maths problem??

mkelly1992 · 2012-09-25 19:33:26

Use factoring to solve the polynomial equation: 2X^3+4x^2-48x=0? can't seem to get the right answer, it isn't x=0,x=-6, x=4. or 2x(x+6)(x-4)=0

25-09-2012 7:33pm

#1

mkelly1992

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Use factoring to solve the polynomial equation: 2X^3+4x^2-48x=0?
can't seem to get the right answer, it isn't x=0,x=-6, x=4. or 2x(x+6)(x-4)=0

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Comments

#2 25-09-2012 7:39pm

bain_triail_as

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2X^3+4x^2-48x=0
is same as x^3+2x^2-24X =0
is same as x(x-4)(x+6)=0
which gives your solution "x=0,x=-6, x=4".

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#3 25-09-2012 7:44pm

mkelly1992

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hmm, maybe the answer key is wrong

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#4 25-09-2012 7:44pm

[Deleted User]
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The solutions are x=-6, x=0 and x=4. Why do you think these aren't correct?

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#5 25-09-2012 8:47pm

TheBody

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Remember folks you can check the answers you get. Just sub each value of x that you found, into the original equation and it should satisfy it if it is correct.

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