\(\dfrac{x-49}{50}+\dfrac{x-50}{49}=\dfrac{49}{x-50}+\dfrac{50}{x-49}\)
\(\Rightarrow\dfrac{x-49}{50}+\dfrac{x-50}{49}-\dfrac{49}{x-50}-\dfrac{50}{x-49}=0\)
\(\Leftrightarrow\left(\dfrac{x-49}{50}-\dfrac{50}{x-49}\right)+\left(\dfrac{x-50}{49}-\dfrac{49}{x-50}\right)=0\)
\(\Leftrightarrow\left(x-49\right)-50+\left(x-50\right)-49=0\)
\(\Leftrightarrow2x-198=0\)
\(\Leftrightarrow x=99\)