Question 456251


{{{x^2 + 8x + 20 = 0 }}}


{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}}


{{{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 }}}


solutions:

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

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

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

or

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

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

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


graph:

{{{ graph( 500, 500, -25, 25, -25, 25,x^2 + 8x + 20) }}}