How do I do this can I get some help please

Answer:
- [tex]$ \frac{\textbf{15}}{\textbf{4}} $[/tex]
Step-by-step explanation:
Given: [tex]$ \frac{3}{4} - \frac{9}{2} $[/tex]
We have to take the denominator equal. We take LCM to make it equal.
[tex]$ \implies \frac{3}{4} - \frac{9 \times 2}{2 \times 2} $[/tex]
[tex]$ = \frac{3}{4} - \frac{18}{4} $[/tex]
[tex]$ = \frac{3 - 18}{4} $[/tex]
[tex]$ = \textbf{-} \frac{\textbf{15}}{\textbf{4}} $[/tex] which is the required answer.