What is the slope of the line?
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The slope of the line may be calculated by using the formula:
m = (y2 - y1)/(x2 - x1), where m is the slope, and (x1, y1) and (x2, y2) are two points on the line.
Using the points (0, -1) and (2, 4) shown, we can substitute these values into the formula above to get:
m = (y2 - y1)/(x2 - x1)
m = (4 - (-1))/(2 - 0)
m = 5/2
Therefor, the slope is 5/2.
Another way to think about the slope is in terms of rise/run, that is for a given interval that the x-value 'runs', by how much does the y value 'rise'?
Here, if we take the same two points (0, -1) and (2, 4), we can see that the x-value has moved 2 units, and the y-value has increased by 5 units. Thus:
if slope = rise/run, then the slope would be 5/2
Note that you should be careful when using this method if the y-value decreases as x increases; in this scenario, the 'rise' would be a negative value rather than a positive one