... you combine (or add) the columns of the matrix {called „A"} as a factor of „x" as illustrated below to obtain a new vector „b" where, in this example, the result is a new point represented by [12 7]. So:
[2 5] [1] [12]
• =
[1 3] [2] [ 7]
• =
[1 3] [2] [ 7]