Solve in integers $\frac{x+y}{x^2-xy+y^2}=\frac{3}{7}$
Solve in positive integers the equation $$m^2 - n^2 - 3n = 5$$
Show that when $x$ is an integer, $x^2 + 5x + 16$ is not divisible by $169$.
Solve in integers $\frac{x+y}{x^2-xy+y^2}=\frac{3}{7}$
Solve in positive integers the equation $$m^2 - n^2 - 3n = 5$$
Show that when $x$ is an integer, $x^2 + 5x + 16$ is not divisible by $169$.