\"\"

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The slope m of a non vertical line through any two points is given by,

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\"\"

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\"\"                              (Substitute 0 for x1, r for x2, 0 for y1 and s for y2)

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\"\"

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\"\"                                    (Subtract: \"\" and \"\")

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Slope \"\"

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\"\"

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The slope m of the line that passes through the pair of points is \"\".