Question 1130087
{{{log((x+20))+log((x))=2}}}


{{{log((x^2+20x))=2}}}



{{{10^2=x^2+20x}}}


{{{x^2+20x-100=0}}}

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{{{x=(-20+sqrt(400+4*100))/2}}}


{{{x=(-20+sqrt(800))/2}}}


{{{x=(-20+10*2*sqrt(2))/2}}}


{{{x=-10+10sqrt(2)}}}