from u1 = 2m, u2 = m, u3 = 5m, and u1-v1 = 3, u2-v2 = 4, u3-v3 = 10 we have:

v1 = u1 - 3 = 2m - 3

v2 = u2 - 4 = m - 4

v3 = u3 - 10 = 5m - 10.

from 2v1 + v2 + 5v3 = 0, we have:

2(2m-3) + m-4 + 5(5m-10) = 0, so

4m - 6 + m - 4 + 25m - 50 = 0

30m = 60

m = 2.

hence u = (4,2,10) and v = (1,-2,0).