Question 181966
{{{x^2-4x(-4)= 0}}} Start with the given equation.



{{{x^2+16x= 0}}} Multiply



{{{x(x+16)=0}}} Factor the left side 



Now set each factor equal to zero:

{{{x=0}}} or  {{{x+16=0}}} 


{{{x=0}}} or  {{{x=-16}}}    Now solve for x in each case



So the answers are 


 {{{x=0}}} or  {{{x=-16}}}