Question

if vector U= (1,-3,-2) and vector V= (4,-5,3) find | u+v-5j |

Answer 1

assuming j = (0,1,0) just do the arithmetic.
This can be done mentally to get u+v-5j = (5,-7,1)
now just take the magnitude of that

Answer 2

u + v = 5 i - 8 j + 1 k
5 j = 0 i + 5 j + 0 k

u + v - 5 j = 5 i - 13 j + 1 k