# How do you graph y=-3x-3?

Jul 6, 2015

The blue line on the graph.

#### Explanation:

We want to draw $y = - 3 x - 3$

Your equation is a linear equation because you can find 2 integers $a$ and $b$ such as : $y = a \cdot x + b$

(Here $a = - 3$ and $b = - 3$)

The representative curve of a linear equation is a straight line!

As you know, we need only 2 points to draw a straight line.

We have to choose 2 points on our equation :

For example $A \left(- 1 , f \left(- 1\right)\right)$ and $B \left(0 , f \left(0\right)\right)$

$f \left(\textcolor{red}{- 1}\right) = - 3 \cdot \left(\textcolor{red}{- 1}\right) - 3 = 3 - 3 = 0$

$f \left(\textcolor{red}{0}\right) = - 3 \cdot \left(\textcolor{red}{0}\right) - 3 = 0 - 3 = - 3$

Now, we know the coordinates of $A$ and $B$ :
$A \left(- 1 , 0\right) , B \left(0 , - 3\right)$

Spot $A$ and $B$ on the graph, and draw the straight line passing by this two points.