Solve the equation 1x+31x+4=16\displaystyle {\frac{{{1}}}{{{x}+{3}}}}-{\frac{{{1}}}{{{x}+{4}}}}={\frac{{{1}}}{{{6}}}}.

The solutions are x1=\displaystyle {x}_{{1}}=   and x2=\displaystyle {x}_{{2}}=  
where x1x2\displaystyle {x}_{{1}}\leq{x}_{{2}}.