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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