[tex]\bf \qquad \qquad \textit{direct proportional variation}\\\\
\textit{\underline{y} varies directly with \underline{x}}\qquad \qquad y=kx\impliedby
\begin{array}{llll}
k=constant\ of\\
\qquad variation
\end{array}\\\\
-------------------------------\\\\
6y=4x^2\implies y=\cfrac{4x^2}{6}\implies y=\cfrac{2x^2}{3}\implies y=\stackrel{k}{\cfrac{2}{3}}x^2[/tex]
