How could you describe a straight vertical line in terms of y?

Question

I asked my Calculus Teacher this and he had no answer, we were talking about linear equations just to brush up on grade 12 maths and I never thought to ask but is it at all possible to describe an equation like x=3 in terms of y? There is no y term in the equation but is there any crazy math to describe it?

Answer 1

Every equation for a line in the $xy$-plane can be put in "standard form" $Ax+By=C$. Vertical lines in particular always can be written in the form $1x+0y=C$. In this case it's usually nicer just to write $x=C$, but you can always interpret it as having an "invisible" $0y$ term.