Question

Answer 1

a. x(x - 2) + x - 2 = 0

<=> (x + 1)(x - 2) = 0

<=> \(\left[{}\begin{matrix}x+1=0\\x-2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=2\end{matrix}\right.\)

Answer 2

b: Ta có: \(2\left(x+3\right)-x^2-3x=0\)

\(\Leftrightarrow\left(x+3\right)\left(2-x\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=2\end{matrix}\right.\)

i: Ta có: \(x^2-5x-14=0\)

\(\Leftrightarrow\left(x-7\right)\left(x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=7\\x=-2\end{matrix}\right.\)