How to find a subspace in $\mathbb{R}^3$ I am having trouble finding if there is a subspace in $\mathbb{R}^3$ for the following question:
$$\{(x,1,0) \, | \, x \, \text{arbitrary numbers}\}$$
What are the steps to solve such a question?
Thanks!
EDIT: 
I am having trouble understanding why this question is being closed. Can someone please explain the reason?

Hint: Subspaces must contain the zero vector. Does this set do that?
To see why it contains the zero vector, notice that if $\vec a$ lies in the subspace, so does $-\vec{a}$. Hence we get $\vec a - \vec a = 0$ as an element.
