$\displaystyle ABCD$ is a trapezium where $\displaystyle AB = 2$, $\displaystyle DC = 3u$ and $\displaystyle AD = v$. $\displaystyle M $is the midpoint of $\displaystyle DC$. Vector $\displaystyle BM$ expreseed in terms of $\displaystyle u$ and $\displaystyle v $is equal to:

A) $\displaystyle v - \frac{3}{4}u$

B) $\displaystyle v - \frac{3}{2}u$

C) $\displaystyle -v + \frac{3}{2}u$

D) $\displaystyle v - \frac{9}{4}u$

E) $\displaystyle -v - \frac{3}{4}$

I have also drawn a diagram for this, but unfortunately I cannot include it in this thread. I am completely useless when it comes to coputers!