Question 259381
{{{7x^2 + 84 = 0}}}
Divide through by 7
{{{x^2+12=0}}}
{{{x^2=-12}}}
{{{x=""+- sqrt(-12)}}}
{{{x=""+- i*sqrt(12)}}}
{{{x=""+- i*sqrt(4*3)}}}
{{{x=""+- i*sqrt(4)*sqrt(3)}}}
{{{x=""+- i*2*sqrt(3)}}}
{{{x=""+- 2*sqrt(3)*i}}}