To solve the equation \( \frac{1}{3}(6x - 9) = -33 \), follow these steps:
- Start by multiplying both sides of the equation by 3 to eliminate the fraction:
\[ 6x - 9 = -33 \cdot 3 \]
This simplifies to:
\[ 6x - 9 = -99 \]
- Next, add 9 to both sides to isolate the term with \( x \):
\[ 6x = -99 + 9 \]
This simplifies to:
\[ 6x = -90 \]
- Finally, divide both sides by 6 to solve for \( x \):
\[ x = \frac{-90}{6} \]
This simplifies to:
\[ x = -15 \]
Thus, the solution is:
\[ \boxed{-15} \]