Question 674236


a quadratic equation could be found with roots like this: Write the roots, a and b, in the form (x-a)(x-b).

{{{(x-a)(x-b)=0}}}

given: {{{a=-1+4i}}} and {{{a=-1-4i}}}..plug it in


{{{(x-(-1+4i))(x-(-1-4i))=0}}}


{{{(x+1-4i)(x+1+4i)=0}}}


{{{x^2+x+4i*x+x+1+4i-4i*x-4i-16i^2=0}}}


{{{x^2+x+cross(4i*x)+x+1+cross(4i)-cross(4i*x)-cross(4i)-16(-1)=0}}}


{{{x^2+x+1+16=0}}}

{{{x^2+x+17=0}}}


{{{ graph( 600, 600, -10, 10, -10, 20, x^2+x+17) }}}