\(x\left(x-2015\right)-\left(x-2015\right)=0\)
\(\left(x-1\right)\left(x-2015\right)=0\)
\(\Rightarrow\orbr{\begin{cases}x-1=0\\x-2015=0\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=1\\x=2015\end{cases}}\)
x(x - 2015) - x + 2015 = 0
<=> x^2 - 2015x - x + 2015 = 0
vì x^2 - 2015x - x + 2015 # 0
=> vô nghiệm