Question

( x - 2/7 ) ( x + 3/4 ) = 0 

Answer 1

`( x - 2/7 ) ( x + 3/4 ) = 0 `

`<=> [(x-2/7 =0),(x+3/4 =0):}`

`<=> [(x=0+2/7),(x=0-3/4):}`

`<=> [(x=2/7),(x=-3/4):}`

Vậy `x in {2/7;-3/4}`

Answer 2

=>x-2/7=0 hoặc x+3/4=0

=>x=2/7 hoặc x=-3/4

Answer 3

`<=>` \(\left[{}\begin{matrix}x-\dfrac{2}{7}=0\\x+\dfrac{3}{4}=0\end{matrix}\right.\)

`<=>` \(\left[{}\begin{matrix}x=\dfrac{2}{7}\\x=-\dfrac{3}{4}\end{matrix}\right.\)