In order to multiply two fractions we just multiply each side of the fraction:
Then, in this case:
[tex]-\frac{6}{11}\cdot\frac{3}{4}=\frac{-6\cdot3}{11\cdot4}=\frac{-18}{44}[/tex]Since 18 and 44 are pair numbers, but can be divided by 2, then we divide both:
[tex]-\frac{18}{44}=-\frac{9}{22}[/tex]