Question

How do you write an equation of a line with Slope = 8, passing through (4, –1)?

Answer 1

We will aim to derive the equation of the line in the standard slope-intercept form `y = mx+c`, where `m` is the slope and `c` is the intercept.

You have already been given `m=8`, so we just need to find `c`.

Subtracting `mx` from both sides of the equation `y = mx+c`, we arrive at:

`c = y - mx`.

We know that one point that satifies this equation is `(4,-1)` since the line passes through it. So we can substitute our known values `m=8`, `x=4` and `y=-1` into this formula to get `c`:

`c = y-mx = -1-(8xx4) = -1-32 = -33`

So the equation of the line is `y = 8x-33`