Question 705658
General form x^2+2x+(p-8)=0


{{{x=(-2-sqrt(4-4(p-8)))/2}}} OR {{{x=(-2+sqrt(4-4(p-8)))/2}}}


Simplifies to
{{{x=-1-sqrt(-7-p)}}} OR {{{x=-1+sqrt(-7-p)}}}


continuing, ...  {{{-sqrt(-7-p)=sqrt(-7-p)}}}, because both roots are specified as equal
{{{0=2*sqrt(-7-p)}}}
{{{0=4*(-7-p)}}}
{{{-28=4p}}}
{{{highlight(p=-7)}}}


x will then be found to be -1,  {{{highlight(x=-1)}}}