Hello, I need help with my homework problem: A certain radioactive (parent) nucleus transforms to a different (daughter) nucleus by emitting an electron and a neutrino. The parent was at rest at the origin of an xy coordinate system. The electron moves away from the origin with linear momentum (-5.8 x 10-22 kg m/s)i; the neutrino moves away from the origin with linear momentum (-2.9 x 10-23 kg m/s)j. What are (a) the magnitude and (b) angle (from the +x axis) of the linear momentum of the daughter nucleus? I easily got part B, but I'm having a problem with part A. They want the momentum, so the equation to use is p=mv. However, I don't know how to get the velocity from the 2 vectors. It seems very easy and it probably is, but I'm not getting the answer right (I tried adding them, etc). I clearly see that i is x-direction and j is y-direction, but that's as far as I can get. I would appreciate it if someone can help. Thanks.