The slope of the line is the ratio of "rise" to "run". That is, it is the ratio of the vertical change between two points to the horizontal change between those points.
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Here, two points are marked, (-1, 2) and (4, -4). Either by counting grid squares or by subtracting coordinates, we find the vertical change (rise) from the first point to the second to be (-4 -2) = -6 units. The horizontal change (run) from the first point to the second is (4 -(-1)) = 5.
