Calculating Reactions A, B, and C for a Solid Desk - Helpful Tips and Solutions

[twoflower]

Hi all!

Homework Statement

What I'm trying to figure out is a reaction of a solid desk (don't know if this is the proper term) given this picture:

http://twoflower.matfyz.cz/inc/eng.gif

I need to compute the reactions A, B and C (they corresponding to points denoted by 'a', 'b' and 'c' on the picture.) The dimensions 'a', 'b' and 'c' are constants and I know them.

The Attempt at a Solution

So far I computed the reaction C from this equation:

$\cos 60 * F_3 + C*\sin 30 = 0$

But I cannot figure out, how to compute the reaction B and A, I can't put the right equations together...

Could someone please point me to the right direction?

Thank you in advance,
best regards.

 

[radou]

Form an equation of the sum of moments with respect to points a and b.