Give an example of a straight line $l$ in $\mathbb R^3$, given by a system of two equations, and a point $(a,b,c)\in \mathbb R^3$ such that there are infinitely many planes in $\mathbb R^3$ passing through $l$ and $(a,b,c)$. Justify your answer.
Straight line defined by $x−y=1,y−z=2$ and point $(1,2,3)$ (from a previous question) rather than point $(1,2,3)$ can we just give any point on the line because as long as its on the straight line there will be infinitely many planes?
Is this correct logic? its a strange question, I have never attempted one like this before so sorry if the answer is trivial.
That point isn't on that line (just plug it in).
Other than that, yes, you could take any point on the line.