3.74: Product of binomial expansions: find $a$, $b$, $c$

The first 3 terms in the expansion of $\left(a + x\right)^{3}\left(1 - \dfrac{x}{3}\right)^{5}$, in ascending powers of $x$, can be written in the form $27 + bx + cx^{2}$, where $a$, $b$ and $c$ are integers. Find the values of $a$, $b$ and $c$.