Question

( 2x + 1) ^ 2= 9

Answer 1

`(2x+1)^2=9`

`=>(2x+1)^2=(3)^2=(-3)^2`

`=>[(2x+1=3),(2x+1=-3):}`

`=>[(2x=2),(2x=-4):}`

`=>[(x=1),(x=-2):}`

Vậy `x=1` hoặc `x=-2`

Answer 2

x = 1

Answer 3

(2x+1)^2=3^2

2x+1=3 hoặc 2x+1=-3

x=1 hoặc x-2

Answer 4

\(\left(2x+1\right)^2=9\Leftrightarrow\left[{}\begin{matrix}2x+1=3\\2x+1=-3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x=2\\2x=-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=-2\end{matrix}\right.\)

Answer 5

Đây nè bạn, chúc ban học tốt :))
    \(\left(2x+1\right)^2=9\)\(\)

⇒\(\left[{}\begin{matrix}2x+1=9\\2x+1=-9\end{matrix}\right.\)   ⇒\(\left[{}\begin{matrix}2x=9-1\\2x=-9-1\end{matrix}\right.\)    

⇒\(\left[{}\begin{matrix}2x=8\\2x=-10\end{matrix}\right.\) ⇒\(\left[{}\begin{matrix}x=8:2\\x=-10:2\end{matrix}\right.\)

⇒\(\left[{}\begin{matrix}x=4\\x=-5\end{matrix}\right.\)