Boxes hanging attached to box on shelf

[whartmann]

Homework Statement

A box of mass m2 = 3.5kg rests on a frictionless horizontal shelf and is attached by strings to boxes of masses m1 = 1.5 kg and m3 = 2.5kg, which hang freely as shown in the figure. The system is initially at rest. After it is released, find A) the tension in each string and B) the acceleration of each box

Homework Equations

Ft = m2a
a = m1g / (m1+m2)

The Attempt at a Solution

Not very sure how to proceed, never done a problem with masses hanging on both sides

 

[Doc Al]

Presumably the strings pass over pulleys? (Diagrams are always helpful.)

Analyze the forces on each mass and apply Newton's 2nd law.