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I'm stuck trying to figure out how I can find out the magnitude of vA and vB when I have the magnitude of vTOT which is vA+vB

I know that the sum of them, vTOT has a speed of 4.5 m/s and speed is the same thing as magnitude pretty much for my purposes in this problem. But I don't know how to use these angles and the other given information to figure out the magnitudes of vA and vB

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    Do you know the law of sines? – 2017-01-14
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    Yeah I forgot to mention that I tried that and it didn't work, so I gave up and came here, thinking that it didn't work with vectors. Do you think I should try it again? – 2017-01-14
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    I did 4.5/sin(131.1) and x/sin(30.8), solved for x and got 3.4698 – 2017-01-14
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    Got it, google was giving me the answer in radians and I forgot this site wanted it in degrees. I was on the right path all along. THanks for clearing this up for me! – 2017-01-14

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Use the Sine Law of triangles: In triangle with sides of length $a_1,a_2,a_3$ that are opposite to angles $A_1,A_2,A_3$ we have $$a_1/\sin A_1=a_2/\sin A_2=a_3/\sin A_3.$$ The 3rd angle in the green triangle is $180^o-30.8^o-18.1^o=131.1^o.$ Therefore $$|v_{tot}|/\sin 131.1^o=|v_A|/\sin 18.1^o=|v_B|/\sin 30.8^o.$$

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    Yep, I already used the sine law but forgot to convert radians to degrees :| – 2017-01-14