$$Ifff(r+5=f(r)+f(5); orov\ P\ th\ o+f(0)=0\ an\ a; f(-5)=-f(5)$$
$\left\{\begin{matrix}x=-\frac{-\sqrt{700fm+3500f+1}+1}{10f}\text{, }&\left(p=-\frac{1}{2}i\text{ or }p=0\right)\text{ and }r=\frac{5}{21}\text{ and }f\neq 0\text{ and }m\neq -5\\x=-\frac{\sqrt{700fm+3500f+1}+1}{10f}\text{, }&\left(p=-\frac{1}{2}i\text{ or }p=0\right)\text{ and }r=\frac{5}{21}\text{ and }f\neq 0\\x=35\left(m+5\right)\text{, }&\left(p=-\frac{1}{2}i\text{ or }p=0\right)\text{ and }m\neq -5\text{ and }f=0\text{ and }r=\frac{5}{21}\end{matrix}\right.$
