To solve for \( y \) in the equation of the line given by \( Ax + By = C \), we need to isolate \( y \).
Starting with the equation:
\[ Ax + By = C \]
- Subtract \( Ax \) from both sides:
\[ By = C - Ax \]
- Now, divide both sides by \( B \) to solve for \( y \):
\[ y = \frac{C - Ax}{B} \]
This simplifies to:
\[ y = \frac{C}{B} - \frac{A}{B}x \]
Among the answer choices provided, the one that matches our derived equation is:
B. \( y = \frac{C}{B} - \frac{A}{B}x \).
So the correct answer is B.