Thanks for your response.

Having said that, I see that their dot products are 0, and I know that that means that they are perpendicular.

**My problem is with the "linear combination" part. Could you please elaborate on that part? More specifically, I know how to find linear combinations of vectors, but I don't understand why the linear combination of a set of vectors that are each perpendicular to a certain vector (vector (a,b,c), in this case) yields another vector that is also perpendicular to that certain vector (vector (a,b,c), in this case).**