What is the slope of the line through the points (2, 3) and (5, 9)?

• A. 1
• B. 3
• C. 2
• D. 4

Answer: (C)

Finding slope means comparing how much the line rises to how much it runs as you move from one point to another. Use rise over run: m = change in y / change in x. From (2, 3) to (5, 9), the rise is 9 − 3 = 6 and the run is 5 − 2 = 3. So the slope is 6/3 = 2. This means the line goes up 2 units for every 1 unit to the right, indicating a positive slope. If the slope were different, the rise and run would have to match that value (for example, a slope of 1 would require the rise to equal the run, which isn’t the case here). The slope you get is 2.