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

Mar 2, 2017

The intercepts are $\left(0 , - 12\right)$ and $\left(3 , 0\right)$. 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

$y = 4 x - 12$

$y = 4 \times 0 - 12$

$y = - 12$

so the $y$ intercept is the point $\left(0 , - 12\right)$

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

$0 = 4 x - 12$

$12 = 4 x$

$\frac{12}{4} = 3 = x$

so the $x$ intercept is at $\left(3 , 0\right)$

Now we have the two points on the graph $\left(0 , - 12\right)$ and $\left(3 , 0\right)$.

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]}