Why use point-slope form for linear equations?

[mathdad]

Why is y = mx + b called the slope-intercept form?

Why is m the chosen variable for slope?

Why is b the chosen variable representing the y-intercept?

 

[Evgeny.Makarov]

Why is y = mx + b called the slope-intercept form?

Because $m$ is the slope and $b$ is the $y$-intercept.

Why is m the chosen variable for slope?

Why is b the chosen variable representing the y-intercept?

If you mean the variable names $m$ and $b$, they are such only in some circles. In Russia, for example, it is customary to denote the slope by $k$, though the intercept is still often denoted by $b$. You are free to call than any names, such as $y=\xi x+\aleph$.

 

[mathdad]

I like s for slope. I guess b is ok for the y-intercept.

I like it this way: y = sx + b or f(x) = sx + b.

 

[Evgeny.Makarov]

I like s for slope.

This makes sense.

 

[mathdad]

For the point-slope, I like y - b = s(x - a), where a and b are the coordinates of the point (a, b).