Question

( 3x + 9 ) ( 11 - x ) = 0

 

Answer 1

vì (3x+9)*(11-x)=0 nên

(3x+9)=0 hoặc (11-x)=0

3x=-9              x=11

x=-9:3

x=0

ĐS : x=0 hoặc x=11

Answer 2

\(\left(3x+9\right)\left(11-x\right)=0\)

\(\Rightarrow\hept{\begin{cases}3x+9=0\\11-x=0\end{cases}\Rightarrow\hept{\begin{cases}3x=-9\\x=11\end{cases}\Rightarrow}\hept{\begin{cases}x=-3\\x=11\end{cases}}}\)

Answer 3

-9:3=-3. mình lộn