How can I shorten this expression? $\frac {-x \cdot a_1 -x\cdot a_2 -x\cdot a_3 -u}{a_4}\cdot l$

Question

I have this fraction: $$\frac {-x \cdot a_1 -x\cdot a_2 -x\cdot a_3 -u}{a_4} \cdot l$$

You see, there are many $-x$ terms. How can I make this shorter? Can I write:

$$x\,\frac { -a_1 -a_2 -a_3}{a_4} \cdot l -u\,\frac { l}{a_4}$$

Is this right?

Regards.

Answer 1

You can do $$\frac{-a_1x-a_2x-a_3x -u}{a_4}l = \left(\frac{-a_1x-a_2x-a_3x}{a_4}-\frac{u}{a_4}\right)l = -x l \frac{a_1 + a_2 + a_3}{a_4} - l \frac{u}{a_4}$$ but there is nothing shorter.