To multiply \( (5x - 15) \) by \( \frac{1}{5} \), you can distribute \( \frac{1}{5} \) to each term inside the parentheses:
\[ \frac{1}{5} \cdot (5x - 15) = \frac{1}{5} \cdot 5x - \frac{1}{5} \cdot 15 \]
Calculating each term:
- \( \frac{1}{5} \cdot 5x = x \)
- \( \frac{1}{5} \cdot 15 = 3 \)
Putting it all together, we have:
\[ x - 3 \]
So, \( (5x - 15) \cdot \frac{1}{5} = x - 3 \).