Question 994286
{{{system(x+y=10,xy=100)}}}


{{{y=10-x}}}
-
{{{x(10-x)=100}}}
{{{-x^2+10x-100=0}}}
{{{x^2-10x+100=0}}}


Formula for general solution of a quadratic equation,
{{{x=(10+- sqrt(10^2-4*100))/2}}}
{{{x=(10+- sqrt(100-400))/2}}}
{{{x=(10+- sqrt(-300))/2}}}--------Complex but not Real Number.


No solution for this case.