Question

The line through point (m,9) and (7,m) has slope m. They yintercept of this line, is

Answer 1

x1, y1) is a known point

m is the slope of the line

(x, y) is any other point on the line

Making sense of it

It is based on the slope:

graph

Slope m = change in ychange in x = y − y1x − x1

Starting with the slope:

we rearrange it like this:

to get this:

equation of line slope rearrange

So, it is just the slope formula in a different way!

Now let us see how to use it.

Example 1:

graph with slope m=3

slope "m" = 31 = 3

y − y1 = m(x − x1)

We know m, and also know that (x1, y1) = (3,2), a