$b)-x-8=-10$

$-x=-10+8$

$-x=-2$

$x=2$

Vậy $x=2$

$c)32-x=-35$

$x=-35-32$

$x=-67$

Vậy $x=-67$

$d)|x|+12=15$

$|x|=15-12$

$|x|=3$

\(\left[ \begin{array}{l}x=3\\x=-3\end{array} \right.\)

$e)18-|x|=20$

$|x|=18-20$

$|x|=-2$

$x∈∅$ vì $|x|≥0$

$f)25-|3-x|=15$

$|3-x|=25-15$

$|3-x|=10$

`⇒` \(\left[ \begin{array}{l}3-x=10\\3-x=-10\end{array} \right.\)

`⇒` \(\left[ \begin{array}{l}x=-7\\x=-13\end{array} \right.\) 

$g)27-|x+5|=30$

$|x+5|=27-30$

$|x+5|=-3$

$⇒$ \(\left[ \begin{array}{l}x+5=-3\\x+5=3\end{array} \right.\) 

`⇒` \(\left[ \begin{array}{l}x=-8\\x=-2\end{array} \right.\) 

$h)17+x-(352-400)=-32$

$17+x-(-152)=-32$

$17+x+152=-32$

$x+169=-32$

$x=-32-169$

$x=-201$

$i)2130-(x+130)+72=-64$

$2130+72-(x+130)=-64$

$2202-(x+130)=-64$

$x+130=2202-(-64)$

$x+130=2202+64$

$x=2266-130$

$x=2136$

$a)\overline{xy}+x+\overline{2y}=5$

$x(y+1)+\overline{2y}+2=5+2$

$x(y+1)+2(y+1)=7$

$(x+2)(y+1)=7$

$x,y∈Ư(7)$

$x,y∈$ `{±1;±7}`

Ta có bảng sau:

$\begin{array}{|c|c|c|}\hline x+2&1&-1&7&-7\\\hline y+1&7&-7&1&-1\\\hline x&-1&-3&5&-9\\\hline y&6&-8&0&-2\\\hline\end{array}$

Vậy các cặp $(x,y)$ là $(-1;6)(-3;-8)(5;0)(-9;-2)$

$b)\overline{xy}-\overline{3x}-y=0$

$x(y-3)-(y-3)=3$

$(x-1)(y-3)=3$

$x,y∈Ư(3)$

$x,y∈$ `{±1;±3}`

Ta có bảng sau:

$\begin{array}{|c|c|c|}\hline x-1&1&-1&3&-3\\\hline y-3&3&-3&1&-1\\\hline x&2&0&4&-2\\\hline y&6&0&4&2\\\hline\end{array}$

Vậy các cặp $(x,y)$ là $(2;6)(0;0)(4;4)(-2;2)$

Gửi ạ !