Question 856134
{{{x^4-10x^2=16 }}}
Complete the square.
{{{x^4-10x^2+25=16+25}}}
{{{(x^2-5)^2=41}}}
{{{(x^2-5)=0 +- sqrt(41)}}}
Use only positive right hand side.
{{{x^2=5+sqrt(41)}}}
{{{x=0 +- sqrt(5+sqrt(41))}}}