Question

Find the equation of the line with slope −2 and that contains the point (−9,−7). Write the equation in the form y=mx+b and identify m and b.

Answer 1

m = -2 which is the slope

b = 2 which is the intercept of the line.

Explanation:

We have that the line must pass through the following points (-9, -7). These two points are any two of the numerous points that pass through the straight line. We can designate variables to each of these points as shown below

Let us take our
`y_1 = -7` and
`x_1 = -9`

Given the slope as
`(y-y_1)/(x-x_1)=-2`

`(y--7)/(x--9) = -2`

`(y +7)/(x+9) =-2`

`y +7 = -2(x+9)`

`y =-2x+2`

We are given the form: y=mx+b.

we can compare this with our equation for the line.
`y =-2x+2`

We can see that m = -2 which is the slope and b = 2 which is the intercept of the line.