Subtract. \[ \frac{7}{2}-\frac{9}{5 d} \] Simplify your answer as much as possible. \( \square \)

To subtract the fractions \( \frac{7}{2} \) and \( \frac{9}{5d} \), we need a common denominator. The least common denominator for 2 and \( 5d \) is \( 10d \). Now, let's rewrite each fraction with the common denominator: \[ \frac{7}{2} = \frac{7 \times 5d}{2 \times 5d} = \frac{35d}{10d} \] \[ \frac{9}{5d} = \frac{9 \times 2}{5d \times 2} = \frac{18}{10d} \] Now we can subtract: \[ \frac{35d}{10d} - \frac{18}{10d} = \frac{35d - 18}{10d} \] Thus, the simplified result of the subtraction is: \[ \frac{35d - 18}{10d} \] So, the final answer is \( \frac{35d - 18}{10d} \).