Calculating Unknown Mass & Speed After Car Collision | Homework Help

[Nitrate]

Homework Statement

Two vehicles traveling as shown collide at an intersection and lock together. Car A ha sa mass of 1000 kg and was traveling east at 40 m/s. Car B has an unknown mass and was headed south at 15 m/s. If the wreckage skids exactly southeast just after the collision, then what is the mass of Car B. Also, what was the initial speed of the wreckage?

Homework Equations

p=mv
Pti = Ptf

The Attempt at a Solution

The thing that is throwing me off with this question is the fact that Car B is of unknown mass. I tried to do trigonometry using the two vectors given, 4000 kg(m/s) [E] and (x)(15 m/s) , but I couldn't seem to work out an answer.

 

[NascentOxygen]

Momentum is a vector quantity. So addition of momentum of A plus momentum of B forms a closed triangle. You are told the angle/s.