# Determining the equation of a line from a graph
Many times, you'll have the graph of an equation shown to you and you'll need to find the equation. This seems a very daunting task, but it's actually quite easy!
We can use the **slope-intercept** formula: **y = mx + b**
- To find b, remember is the point when the line crosses the
*y* axis
- To find the value of the slope, you compute the
*rise* over the *run*.
Remember you can also determine the equation of a line from its graph if you get two points of the line.
Find the equation of the line:
We can calculate m because the line goes through points (-2,0) and (0,3). That is
.
We can calculate b because the y-intercept point is (0,3). That is b=3.
The equation of the line is:
.
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