How do i write an equation for the line parallel to the x-axis through the point (0,-1?

Parallel to the x axis so x is constant and we'll have different y values
the 0 vector is a on the x axis as well so let's try it with that

y=-mx+b

This is what i found “an explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location). it defines the sequence as a formula in terms of n. this example is an arithmetic sequence(the same number, 5, is added to each term to get to the next term).” i hope this you for what your looking for. can you plz mark me brainliest?