Question 254002
We have this:
{{{ x^2-8x-11=0 }}} 
If we apply quadratic, we get
{{{x = (8 +- sqrt( 64-4*1*(-11)))/(2) }}}
and then
{{{(8 +- sqrt(108)) /  2}}}
and finally
{{{x = (8 +- 6sqrt(3 ))/(2) }}}
divide every outside number by 2 to get
{{{x = 4 +- 3sqrt(3)}}}