Question 1074509
3x*(x^2+3x-28)/(x^4-3x^3+7x^2+11x-56)=0 
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That fraction is zero when the numerator is zero::
Solve:: 3x(x-7)(x+4) = 0
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x = 0 or x = 7 or x = -4
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Cheers,
Stan H.
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