<PRE><B>Question 598315</B>
I need help factoring out this problem{{{20x^3+16x^2+25x+20=0}}}
I did it in two group
(20x^3+16x^2) (25x+20)=0
4x^2(5x+4)     5(5x+4)=0
(5x+4)  (4x^2+5)=0
5x+4=0
5x+4-4=0-4
5x=-4
divide x= -4/5
I could not factor out (4x^2+5)=0 
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4x^2 + 5 = 0
4x^2 = -5
x^2 = -5/4
{{{x = 0 +- sqrt(5)i/2}}}
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i = sqrt(-1)
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