Precalculus, Chapter 6, 6.3, Section 6.3, Problem 34

You need to evaluate the sum of two vectors,u+v , hence you need to perform the addition of the same versors, such that:
u = <0,0> => u = 0i + 0j
v = <2,1> => v = 2i + j
u + v = <0,0> + <2,1>
u + v = <0+2,0+1> => u + v = <2,1>
Hence, evaluating the sum u + v yields u + v = <2,1>
You need to evaluate the difference of two vectors,u-v, hence you need to perform the subtraction of the same versors, such that:
u - v = <0,0> - <2,1>
u - v = <0-2,0-1> => u - v = <-2,-1>
Hence, evaluating the difference u - v yields u - v = <-2,-1> .
You need to evaluate the difference of the vectors,2u-3v , hence you need to perform first the multiplication of each vector with the indicated scalar and then you need to perform the subtraction of the same versors, such that:
2u - 3v = 2<0,0> - 3<2,1>
2u - 3v = <2*0,2*0> - <3*2,3*1>
2u - 3v = <2*0 - 3*2,2*0 - 3*1> => 2u - 3v = <-6,-3>
Hence, evaluating the difference 2u - 3v yields 2u - 3v = <-6,-3>.