Question

3x+15/x^2-25 + 3/x+5 = 2x/x-5

Answer 1

\(\Leftrightarrow3x+15+3\left(x-5\right)=2x^2+10x\)

\(\Leftrightarrow2x^2+10x=3x+15+3x-15=6x\)

=>2x(x+2)=0

=>x=0 hoặc x=-2

Answer 2

\(\dfrac{3x+15}{x^2-25}+\dfrac{3}{x+5}=\dfrac{2x}{x-5}\)

\(ĐK:x\ne\pm5\)

\(\Leftrightarrow\dfrac{3x+15+3\left(x-5\right)}{\left(x-5\right)\left(x+5\right)}=\dfrac{2x\left(x+5\right)}{\left(x-5\right)\left(x+5\right)}\)

\(\Leftrightarrow3x+15+3\left(x-5\right)=2x\left(x+5\right)\)

\(\Leftrightarrow3x+15+3x-15=2x^2+10x\)

\(\Leftrightarrow2x^2+4x=0\)

\(\Leftrightarrow2x\left(x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-2\end{matrix}\right.\) ( tm )