`\color{blue}\text {_Namm_}`
`a, x \div 27=-2 \div 3,6`
`x \div 27=-5/9`
`x=-5/9 *27`
`x=-15`
`b, (2x+1)*(2x+1)=27*3`
`(2x+1)^2=81`
`(2x+1)^2=(+-9)^2`
`->`\(\left[{}\begin{matrix}2x+1=9\\2x+1=-9\end{matrix}\right.\)
\(\rightarrow\left[{}\begin{matrix}2x=9-1\\2x=-9-1\end{matrix}\right.\)
\(\rightarrow\left[{}\begin{matrix}2x=8\\2x=-10\end{matrix}\right.\)
\(\rightarrow\left[{}\begin{matrix}x=8\div2=4\\x=-10\div2=-5\end{matrix}\right.\)
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