The image you uploaded contains math problems on multiplying and dividing rational expressions. Let me extract the details and help you solve them. Please give me a moment.Here are the exercises based on multiplying and dividing rational expressions in the image:

1. $\frac{x^2}{45 - 20x} \times \frac{3 - x}{x - 2}$
2. $\frac{3}{7} \div \frac{x}{x + 1}$
3. $\frac{3x^2}{x - 2} \times \frac{x + 5}{3x + 15}$
4. $\frac{3x - 9}{x + 3} \div \frac{x - 3}{x + 4}$
5. $\frac{x^2 - 9x}{4} \times \frac{1}{x - 7}$
6. $\frac{x^2 + x}{x + 7} \times \frac{x^2 + 7x}{x^2}$

Would you like me to go through the solution steps for each?