Question

Y=mx+b

Answer 1

Yes, although 10/.5 = 20.

Answer 2

Just a meaningless input but,  throughout all of my maths education it's been either:

Y=\alpha x+\beta  because stats

Or

Y=mx+c  because calculus

 (always remember +c, or - c to be an edge Lord, not like it really matters as eventually you just have to evaluate your integrals meaning the +c was just an excuse for high school teachers to call you out in front of everybody lol

Your version is completely acceptable and true, but it disturbs me... Its not natural!