Question 656149
{{{x^2+8x+20=0}}}...use quadratic formula to solve for {{{x}}}


{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} ...note that {{{a=1}}}, {{{b=8}}} and {{{c=20}}}


{{{x = (-8 +- sqrt( 8^2-4*1*20 ))/(2*1) }}}


{{{x = (-8 +- sqrt( 64-80 ))/2 }}}


{{{x = (-8 +- sqrt( -16 ))/2 }}}


{{{x = (-8 +- sqrt( -1*16 ))/2 }}}


{{{x = (-8 +- 4i)/2 }}}


{{{x = -8/2 +- 4i/2 }}}


{{{x = -4 +- 2i }}}


solutions:

{{{x = -4 + 2i }}}
or
{{{x = -4 - 2i }}}


{{{ graph( 600, 600, -10, 10, -5, 25, x^2+8x+20) }}}