\(\dfrac{x-3}{x+3}=\dfrac{x^2}{x^2-9}\left(ĐKXĐ:x\ne\pm3\right)\)
\(\Leftrightarrow\dfrac{x-3}{x+3}-\dfrac{x^2}{\left(x-3\right)\left(x+3\right)}=0\)
\(\Leftrightarrow\dfrac{\left(x-3\right)^2}{\left(x-3\right)\left(x+3\right)}-\dfrac{x^2}{\left(x-3\right)\left(x+3\right)}=0\)
\(\Leftrightarrow\dfrac{x^2-6x+9}{\left(x-3\right)\left(x+3\right)}-\dfrac{x^2}{\left(x-3\right)\left(x+3\right)}=0\)
\(\Rightarrow x^2-6x+9-x^2=0\)
\(\Leftrightarrow-6x+9=0\)
\(\Leftrightarrow-6x=-9\)
\(\Leftrightarrow x=\dfrac{3}{2}\left(tm\right)\)
=>(x-3)^2=x^2
=>-6x+9=0
=>6x=9
=>x=3/2
