Quadratic Function with Given Vertex and Point

Consider a quadratic function defined by the equation:

$$ f(x) = ax^2 + bx + c $$

where the function has its vertex at the point (3, -2) and passes through the point (0, 1). Furthermore, it is given that $a < 0$. Determine the value of $a + b + c$ and provide it as a grid-in response, rounding your answer to two decimal places, if necessary.