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Find the constant of variation of the equation. \ \

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The statement varies directly as , means that when increases, increases by the same factor.

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Hence and always have the same ratio.

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The constant of variation of the equation and the slope of the line have the same value.

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                  (Direct variation formula) 

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Find .

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              (Substitute and )

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                  (Simplify)

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Therefore,  the direct variation of the equation is .

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Find when .

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                (Direct variation of the equation)

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             (Substitute )

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        (Divide each side by )

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                      (Cancel common terms)

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