Question

How do you graph the line that goes through the point (0, 9) and has a slope of -4?

Answer 1

See explanation

Explanation:

First we must find the equation of the line. Since we know the slope of the line and a point, we can use the point-slope formula to determine the equation of the line.

Point-slope formula: `y-y_1=m(x-x_1)` where `m=-4`, and `(0,9)-> (x_1,y_1)`

Substituting these values...

`y-9=-4(x-0)`

`ycancel(-9+9)=-4x+9`

`y=-4x+9`

Now that we have the equation of the line, we can graph the line either using a graphing calculator or by plotting point via a table.

If we create a table:

`x" | "y`

`0" | "9`
`1" | " 5`
`2" | " 1`
`3 " | " -3`

And etc.

Once we plot those points we can draw a line through the points since this is a linear function. The graph should look something like this.

graph{-4x+9 [-10, 10, -5, 5]}