\(\frac{x-3}{25}=\frac{-1}{3-x}\)
\(\Rightarrow-\left(x-3\right)\cdot\left(3-x\right)=1\cdot25\)
\(\Rightarrow\left(x-3\right)\left(x-3\right)=25\)
\(\Rightarrow\left(x-3\right)^2=25\)
\(\Rightarrow\left[\begin{array}{nghiempt}x-3=5\\x-3=-5\end{array}\right.\)\(\Leftrightarrow\left[\begin{array}{nghiempt}x=8\\x=-2\end{array}\right.\)
\(\Rightarrow\left(x+3\right)\left(x-3\right)=-25\)
\(\Rightarrow\left(x+3\right)\left(-1\right)\left(x+3\right)=-25\)
\(\Rightarrow\left(x+3\right)^2=25\)
\(\Rightarrow\left[\begin{array}{nghiempt}x+3=5\\x+3=-5\end{array}\right.\)\(\Rightarrow\left[\begin{array}{nghiempt}x=2\\x=-8\end{array}\right.\)
