Question 335690
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
{{{x = (-(-4) +- sqrt( (-4)^2-4*1*(-7) ))/(2*1) }}} 
{{{x = (4 +- sqrt( 16+28 ))/2 }}} 
{{{x = (4 +- sqrt( 44))/2 }}} 
{{{x = (4 +- sqrt( 4*11))/2 }}} 
{{{x = (4 +- sqrt( 4)*sqrt(11))/2 }}} 
{{{x = (4 +- 2*sqrt(11))/2 }}} 
{{{x = 2 +- sqrt(11) }}}