Question

look at this graph: write the equation of the line.

Explanation:

Step1: Recall line - equation form

The general form of a horizontal line is $y = b$, where $b$ is the $y$ - coordinate of all points on the line.

Step2: Identify $y$ - coordinate

From the graph, all points on the line have a $y$ - coordinate of $- 40$.

Answer:

$y=-40$