Suppose B is a vector and equal to (a,b,c,d) and also suppose that B lies in the span of (1,0,2,1), (-2,3,-1,1) and (2,-2,1,-1). What conditions must a,b,c and d satisfy?
This is something that i have no idea how to approach. i know the answer is a - c + d = 0 but i don't know how to get to this answer.
can anyone point me in the right direction?