Question

How do you graph `y=4x-12` using intercepts?

Answer 1

The intercepts are `(0,-12)` and `(3,0)`. The graph is a straight line through these two points.

Explanation:

An intercept is a point when a line crosses an axis. Mathematically, this is where one of the coordinates is equal to `0` - when it crosses the `y` axis the `x` coordinate is `0`, and when it crosses the `x` axis the `y` coordinate is `0`.

The `y` intercept is found by setting `x=0` in the equation, so

`y=4x-12`

`y=4xx0-12`

`y=-12`

so the `y` intercept is the point `(0,-12)`

The `x` intercept is found by setting `y=0` and solving, so

`0=4x-12`

`12=4x`

`12/4=3=x`

so the `x` intercept is at `(3,0)`

Now we have the two points on the graph `(0,-12)` and `(3,0)`.

Since it is a straight line graph, simply connect the dots and draw a long line.

It should look something like this

graph{4x-12 [-10, 10, -20, 20]}