Calculate evenly distributed force on a beam

[dreamliner]

If you have a beam with a force q evenly distributed on top of it, would this

ƩMA= 0 B*3,3-Cy*5,5-q*4,3*2,15=0

or this

ƩMA=0 B*3,3-Cy*5,5-q*4,3*2,15*3,35=0

be the right way to set up the moment point calculations? Basically what I'm unsure of is if I must incorporate the distance from q to the moment point in A and if so to use the entire distance q is working on+the distance from the beginning of q to point A, or to use the distance from the median of q to point A...

Hastily drawn up figure in order to illustrate what I mean:

 

[PhanthomJay]

It is from the median (CG of the load) to A but you didn't calculate that distance correctly, or maybe just a typo error