Đáp án:
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Giải thích các bước giải:
`a,17+x-(352-400)=-32`
`⇔x-(-48)=-32-17`
`⇔x+48=-49`
`⇔x=-49-48`
`⇔x=-97`
Vậy `x=-97`
,
`b,2130-(x+130)+72=-64`
`⇔2130-x-130+72=-64`
`⇔-x=-64-2130+130-72`
`⇔-x=-2136`
`⇔x=2136`
Vậy `x=2136`
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`c,|x|-5=-1`
`⇔|x|=-1+5`
`⇔|x|=4`
\(⇔\left[ \begin{array}{l}x=4\\x=-4\end{array} \right.\)
Vậy `x=4` hoặc `x=-4`
,
`d,|x+2|-13=-1`
`⇔|x+2|=-1+13`
`⇔|x+2|=12`
\(⇔\left[ \begin{array}{l}x+2=12\\x+2=-12\end{array} \right.\)
\(⇔\left[ \begin{array}{l}x=12-2\\x=-12-2\end{array} \right.\)
\(⇔\left[ \begin{array}{l}x=10\\x=-14\end{array} \right.\)
Vậy `x=10` hoặc `x=-14`
,
`e,135-|9-x|=35`
`⇔|9-x|=135-35`
`⇔|9-x|=100`
\(⇔\left[ \begin{array}{l}9-x=100\\9-x=-100\end{array} \right.\)
\(⇔\left[ \begin{array}{l}-x=100-9\\-x=-100-9\end{array} \right.\)
\(⇔\left[ \begin{array}{l}-x=91\\-x=-109\end{array} \right.\)
\(⇔\left[ \begin{array}{l}x=-91\\x=109\end{array} \right.\)
Vậy `x=-91` hoặc `x=109`
,
`f,||x-5|-3|=9`
`*TH_1:|x-5|-3=9`
`⇔|x-5|=9+3`
`⇔|x-5|=12`
\(⇔\left[ \begin{array}{l}x-5=12\\x-5=-12\end{array} \right.\)
\(⇔\left[ \begin{array}{l}x=12+5\\x=-12+5\end{array} \right.\)
\(⇔\left[ \begin{array}{l}x=17\\x=-7\end{array} \right.\)
`*TH_2:|x-5|-3=-9`
`⇔|x-5|=-9+3`
`⇔|x-5|=-6` ( Vô lý)
Vậy `x=17` hoặc `x=-7`
