3.72: Linear law: $e^{5y}$ against $x^{3}$

When $e^{5y}$ is plotted against $x^{3}$, a straight line through $(-2.56, 4.38)$ and $(6.54, 9.84)$ is obtained. Find $y$ in terms of $x$.

Find the values of $x$ for which $y$ can exist.