WEBVTT

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For this original example, enter x subscript one equals the list one, two, three, four.

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On the next line enter y subscript one equals five, seven, nine, eleven.

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Type y subscript one, then press the right arrow to leave the subscript.

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Enter tilde m x subscript one, press the right arrow again, and add b.

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The tilde asks Desmos to fit a model to paired data.

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An equals sign does not perform this regression.

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The regression parameters show m equals two and b equals three.

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Plot the ordered-pair lists x subscript one, y subscript one to see the four data points.

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Their y values increase by two each time x increases by one.

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Substituting the first point into y equals two x plus b gives b equals three.

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Here every point lies exactly on y equals two x plus three, so R squared equals one.

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Real data may have residuals.

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A fitted relationship does not establish causation or justify extrapolation beyond the studied range.