To evaluate the expression \( df + d \) for \( d = -3 \) and \( f = 4.9 \), we first calculate \( df \):
\[ df = d \cdot f = -3 \cdot 4.9 \]
Now, calculate that:
\[ -3 \cdot 4.9 = -14.7 \]
Next, we add \( d \) to this result:
\[ df + d = -14.7 + (-3) \]
Calculating that gives:
\[ -14.7 - 3 = -17.7 \]
Thus, the evaluated expression is:
\[ \boxed{-17.7} \]