I already posted one of these proofs, but I figured I would combine the rest into an album and submit them at once.

The questions is to prove if the given subsets are a subspace of R^3.

I'm confident that I did a and b well enough. For c, I did not know how to handle the inequality, so I did what I thought was best. I am also worried because it says to prove or disprove, and all mine are proofs..

I would appreciate any feed back on my proofs.

https://imgur.com/a/LYHEptt