# Origin of y=mx+b

1. Feb 10, 2009

### Liger20

Hello, could someone please explain to me why the equation y=mx+b uses 'm' for slope and 'b' for y-intercept? This has always bothered me for some reason.

2. Feb 10, 2009

### symbolipoint

"m" comes from "mont", or "mount", or some french or latinized word meaning mountain, or sloping grade. The "b", I'm not sure about. Maybe (just a wild guess) base, bass, some word meaning low point, like where the "mountain" meets the "flat". I'm more certain about the "m" for "mont" as the slope.

3. Feb 10, 2009

### Nabeshin

The b problably comes from the fact that polynomials are typically written y=ax^n+bx^n-1+cx^n-2 etc. But the special case of a linear polynomial a=m (from what symboipoint said) and the b probably just stayed.

4. Feb 11, 2009

### csprof2000

In Italy, they don't use b, they use q.

5. Feb 11, 2009

### arildno

In norway, m is called a.

6. Feb 13, 2009

### Nancarrow

And in Britain, 'b' is called 'c'!

7. Feb 13, 2009

### HallsofIvy

Staff Emeritus
Wow, you guys have really strange alphabets!

8. Feb 13, 2009

### Tac-Tics

I always enjoyed $$n \cdot p_0 = n \cdot \left[ \begin{array}{c}x\\y\end{array} \right]$$