Question 8979
{{{x^3 - 8 = 0}}}  Factors into
{{{ (x-2)(x^2 + 2x + 4) = 0 }}}


The quadratic factor can be solved by either the quadratic formula, the pluggable solver, or by completing the square.  Completing the square is fairly easy: 
{{{x^2 + 2x + _____ = -4 + ____ }}}
{{{x^2 + 2x + 1     = -4 + 1 }}}
{{{ (x+1)^2 = -3 }}}
{{{  (x+1) = sqrt(-3) }}}
{{{ x = -1 +- i *sqrt(3) }}}, and of course, x=2!!


R^2