Question 740085


{{{ ln(x)+ln(x+3)=ln(10)}}}


{{{ ln(x(x+3))=ln(10)}}}


{{{x(x+3)=10}}}

{{{x^2+3x=10}}}

{{{x^2+3x-10=0}}}


{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}


{{{x = (-3 +- sqrt( 3^2-4*1*(-10) ))/(2*1) }}}

{{{x = (-3 +- sqrt( 9+40 ))/2 }}}

{{{x = (-3 +- sqrt( 49 ))/2 }}}

{{{x = (-3 +- 7)/2 }}}

solution: we need only positive solution

{{{x = (-3 + 7)/2 }}}

{{{x = 4/2 }}}

{{{x = 2 }}}