Locate two points on the graph. Look for points with coordinates that are integers. We can choose any points, but we will use (0, 5) and (3, 3). Starting with the point on the left, sketch a right triangle, with the hypotenuse going from the first point to the second point.
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| Count the rise – it is negative. |
The rise is −2. |
| Count the run. |
The run is 3. |
| Use the slope formula. |
m=runrise |
| Substitute the values of the rise and run. |
m=3−2 |
| Simplify. |
m=−32 |
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The slope of the line is −32. |
Notice that the slope is negative since the line slants downward from left to right.
What if we had chosen different points? Let’s find the slope of the line again, this time using different points. We will use the points (−3,7) and (6,1).

Starting at (−3,7), sketch a right triangle to (6,1).
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| Count the rise. |
The rise is −6. |
| Count the run. |
The run is 9. |
| Use the slope formula. |
m=runrise |
| Substitute the values of the rise and run. |
m=9−6 |
| Simplify the fraction. |
m=−32 |
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The slope of the line is −32. |
It does not matter which points you use—the slope of the line is always the same. The slope of a line is constant!