Question

How do you write an equation of a line given (3,-1), m=-3?

Answer 1

`y=-3x+8`

Explanation:

We have
`y=-3x+n`
For `x=3,y=-1`
we get
`-1=-9+n`
so `n=8`

Answer 2

`y=-3x+8`

Explanation:

`"the equation of a line in "color(blue)"slope-intercept form"` is.

`•color(white)(x)y=mx+b`

`"where m is the slope and b the y-intercept"`

`"here "m=-3`

`y=-3x+blarrcolor(blue)"is the partial equation"`

`"to find b substitute "(3,-1)" into the partial equation"`

`-1=-9+brArrb=-1+9=8`

`y=-3x+8larrcolor(red)" is equation of line"`