[tex]\bf \begin{array}{ccll}
x&y\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
0&\stackrel{0\times 4}{0}\\\\
1&\stackrel{1\times 4}{4}\\\\
2&\stackrel{2\times 4}{8}\\\\
3&\stackrel{3\times 4}{12}\\
------&------\\
x&y=x\times 4\\
&y=4x
\end{array}[/tex]
