While working with the first Interactive Activity, choose different pairs of points. For each pair, it's important that the difference between the y coordinates and the difference between the x coordinates are computed by considering the pairs in the same order. That is, for points (x1, y1) and (x2, y2), the slope can be computed as either
(y1 - y2) / (x1 - x2) or (y2 - y1) / (x2 - x1).
Note that students sometimes confuse this by computing (y2 - y1) / (x1 - x2).
<< back to Part B: Slope
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