Question

How do I solve 8, 9, and 10?

Answer 1

8)

`y-8=m(x+6)\\y-8=(-4)/(3)(x+6)\\\\y=(-4)/(3)x`

9)

`y+4.5=mx\\y=15x-4.5`

10)

`y+1=m(x-1)\\y=-2(x-1)-1\\y=-2x+1`

Explanation:

We can use the definition of a line:

`y-y_0=m(x-x_0)`

where
`y_0` and
`x_0` co-ordinates of a point on that line, and where
`m` is the gradient of the line.

We can work out the gradient of the line by looking at the differential, or the change in y compared to the change in x.

`m=(\Delta y)/(\Delta x) = (y_1-y_0)/(x_1-x_0)`

where
`(x_0,y_0)` and
`(x_1,y_1)` are two distinct points on the line.

You now have the tools needed to go about answering these questions!