Relative acceleration; Wedge problem!!!

[TheShockgloss]

A wedge of mass M has two inclined surfaces φ to the horizontal. This is kept on a smooth flat surface. masses 2m(A) and m(B) are kept on one surface connected by a movable pulley(D) on one inclined surface. The pulley is connected to another m(C) mass on the other inclined surface by another string.
(strings - mass-less and in extensible) (Pulley is mass-less) (Wedge moves without friction)
If the system was released from rest;
Show that the a(D,A) = (2 g sin φ) / 11
a(Wedge,Earth) = 18mgsinφcosφ / 11(M + 4msin²φ)

Please.........solve this!!! I tried it a several times. Could not work it out..... PLEASE!
I'm allowed to use a(X,Y) = a(X,Z) + (Z,Y)

 

[stapel]

Please.........solve this!!! I tried it a several times.

Please reply with a sample of what you've tried, so the helpers can see what you're doing. Thank you!

 

[DrPhil]

A wedge of mass M has two inclined surfaces φ to the horizontal. This is kept on a smooth flat surface. masses 2m(A) and m(B) are kept on one surface connected by a movable pulley(D) on one inclined surface. The pulley is connected to another m(C) mass on the other inclined surface by another string.
(strings - mass-less and in extensible) (Pulley is mass-less) (Wedge moves without friction)
If the system was released from rest;
Show that the a(D,A) = (2 g sin φ) / 11
a(Wedge,Earth) = 18mgsinφcosφ / 11(M + 4msin²φ)

Please.........solve this!!! I tried it a several times. Could not work it out..... PLEASE!
I'm allowed to use a(X,Y) = a(X,Z) + a(Z,Y)

We need to see your work to know what level of math you are using .. are you expected to use vector algebra, or calculus and differential equations?

The only hint I can see to give you is that the sum of all vertical forces is (M+4m)g, which is balanced by the force upward on the base of the wedge. Have you conserved energy? What about the momentum vector?

If you have pictures in jpeg or gif (I don't know what others) format, you can use the "Insert Image" tool on the middle toolbar to upload them. You have done a very good job describing the arrangement of pulleys in words, but we may need detailed diagrams of the force vectors on each mass.