Question

(1/2.x-7).(x+2)=0

tìm x

Answer 1

`(1/2x-7)(x+2)=0`

`<=>` \(\left[ \begin{array}{l}\dfrac12x-7=0\\x+2=0\end{array} \right.\) 

`<=>` \(\left[ \begin{array}{l}\dfrac12x=7\\x=-2\end{array} \right.\) 

`<=>` \(\left[ \begin{array}{l}x=14\\x=-2\end{array} \right.\) 

Vậy `x=14` hoặc `x=-2`

Answer 2

Ta có: \(\left(\dfrac{1}{2}x-7\right)\left(x+2\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}\dfrac{1}{2}x-7=0\\x+2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=14\\x=-2\end{matrix}\right.\)