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\begin{enumerate}
\item ���̕������������Ȃ����B

\begin{enumerate}
\item $x-2=-8$

{\color{white}{$x=-8+2$}}

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\item $\dfrac{1}{\,3\,}x=-6$

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\item $2x+1=9$

\hspace{-15mm}���v�Z��

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$2x$ & $\>=\>$ & $8$
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\item $7x-24=2x+11$

\hspace{-15mm}���v�Z��

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$7x-2x$ & $\>=\>$ & $11+24$ \\
$5x$ & $\>=\>$ & $35$ \\
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\item $5x-7(x-2)=2$

\hspace{-15mm}���v�Z��

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$5x-7x+14$ & $\>=\>$ & $2$ \\
$-2x$ & $\>=\>$ & $-12$ \\
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\item $0.25x=0.2x-0.1$

\hspace{-15mm}���v�Z��

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$0.25x\times 100$ & $\>=\>$ & $(0.2x-0.1)\times 100$ \\
$25x$ & $\>=\>$ & $20x-10$ \\
$5x$ & $\>=\>$ & $-10$ \\
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\item $\dfrac{1}{\,4\,}x-\dfrac{1}{\,3\,}=\dfrac{2}{\,3\,}x+\dfrac{1}{\,2\,}$

\hspace{-15mm}���v�Z��

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$\Bigl(\dfrac{1}{\,4\,}x-\dfrac{1}{\,3\,}\Bigl)\times 12$ & $\>=\>$ & $\Bigl(\dfrac{2}{\,3\,}x+\dfrac{1}{\,2\,}\Bigl)\times 12$ \\
$3x-4$ & $\>=\>$ & $8x+6$ \\
$-5x$ & $\>=\>$ & $10$ \\
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\item $\dfrac{\,x-6\,}{2}=\dfrac{\,2x-1\,}{5}$

\hspace{-15mm}���v�Z��

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$\dfrac{\,x-6\,}{2}\times 10$ & $\>=\>$ & $\dfrac{\,2x-1\,}{5}\times 10$ \\
$5(x-6)$ & $\>=\>$ & $2(2x-1)$ \\
$5x-30$ & $\>=\>$ & $4x-2$ \\
$5x-4x$ & $\>=\>$ & $-2+30$ \\
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\end{enumerate}

\item ���̔�Ꭾ�������Ȃ����B

\begin{enumerate}
\item $x\,:\,8=7\,:\,12$

{\color{white}{
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$12x$ & $\>=\>$ & $56$ \\
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\newpage

\item $(x-6)\,:\,21=4\,:\,7$

{\color{white}{
\hspace{-1.5mm}
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$7(x-6)$ & $\>=\>$ & $84$ \\
$7x-42$ & $\>=\>$ & $84$ \\
$7x$ & $\>=\>$ & $126$ \\
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}}

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\end{enumerate}

\item $x$�ɂ��Ă̕�����\,$2x+a=4x+1$\,�̉���$2$�ł���Ƃ��C$a$�̒l�����߂Ȃ����B

{\color{white}{
\hspace{-1.5mm}
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\multicolumn{3}{l}{$x=2$����}\\
$2\times 2+a$ & $\>=\>$ & $4\times 2+1$ \\
$4+a$ & $\>=\>$ & $9$ \\
$a$ & $\>=\>$ & $5$ \\
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\item �g��$160$\ajLig{cm}�̑��Y�N�̉e�̒���$2.5$\ajLig{m}�ł����B���̂Ƃ��e�̒�����$7.5$\ajLig{m}�̖؂̍����͉�\ajLig{m}�ł����B

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\hspace{80mm}  \\[-8pt]
\color{white}{�؂̍�����$x$\ajLig{m}�Ƃ���B}\\
\color{white}{
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$x\,:\,7.5$ & $\,=\,$ & $1.6\,:\,2.5$ \\
$2.5x$ & $=$ & $7.5\times 1.6$ \\
$x$ & $=$ & $\dfrac{\,7.5\times 1.6\,}{2.5}$ \\
$x$ & $=$ & $4.8$ \\
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\multicolumn{1}{|r|}{\underline{\color{white}{~~~4.8~~~}~~~}\ajLig{m}}
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\\
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\vspace{1mm}
\item 2�����̐���������܂��B���̈�̈ʐ�����8�ŁC��̈ʂƏ\�̈ʂ̐�������ꂩ���Ăł��鐔�́C���Ƃ̐����27�傫���ł��B
���Ƃ̐����������p���ċ��߂Ȃ����B

\vspace{1mm}
\underline{\color{white}{���Ƃ̐��̏\�̈�}}��$x$�Ƃ���B

\vspace{2mm}
\begin{tabular}{|@{\vrule width 0.3pt \hspace{2.5mm}}c|@{\vrule width 0.3pt}}
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\hspace{80mm}  \\[-12pt]
\color{white}{
\begin{tabular}{r@{}c@{}l}
$(80+x)-(10x+8)$ & $\,=\,$ & $27$ \\
$80+x-10x-8$ & $=$ & $27$ \\
$-9x$ & $=$ & $27-72$ \\
$-9x$ & $=$ & $-45$ \\
$x$ & $=$ & $5$ \\
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}\\[-12pt]
\multicolumn{1}{|r|}{\underline{\color{white}{~~~~~58~~~~~}}}
\\[-12pt]
\\
\noalign{\hrule height 0.3pt}\hline
\end{tabular}

\item �g���b�N���������H��$\mathrm{A}$�n�_��$10$���ɏo�����C����$1$���Ԍ�ɏ�p�Ԃ�����$\mathrm{A}$�n�_���o�����܂����B
�g���b�N�̑���������$60$\ajLig{km}�C��p�Ԃ̑���������$100$\ajLig{km}�Ƃ���Ƃ��C���������ɏ�p�Ԃ̓g���b�N�ɒǂ����܂����B
��������p���ċ��߂Ȃ����B

\vspace{1mm}
\underline{\color{white}{��p�Ԃ��ǂ����܂ł̎���}}��$x$�Ƃ���B

\vspace{1mm}
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\noalign{\hrule height 0.3pt}\hline
\hspace{80mm}  \\[-12pt]
\color{white}{
\begin{tabular}{r@{}c@{}l}
$60(x+1)$ & $\,=\,$ & $100x$ \\
$60x+60$ & $=$ & $100x$ \\
$-40x$ & $=$ & $-60$ \\
$x$ & $=$ & $\dfrac{\,3\,}{2}$ \\
\end{tabular}
}\\
\\
\multicolumn{1}{|r|}{\underline{\color{white}{~~~$12$��$30$��~~~}}}
\\[-12pt]
\\
\noalign{\hrule height 0.3pt}\hline
\end{tabular}

\end{enumerate}

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