If the original equation of the graph is \( y = \frac{2}{3}x \) and the graph is shifted 3 units up, the new equation would be obtained by adding 3 to the original equation.
Thus, the new equation becomes:
\[ y = \frac{2}{3}x + 3 \]
Among the given options, this corresponds to:
y = \frac{2}{3}x + 3
So the correct response is:
y is equal to \(\frac{2}{3}x + 3\).