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Help me pleaseif y varies directly with X, find a missing value below .(3, -39) and (x, 65)

User Atiretoo
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We are told that y varies directly with x and are given that the following (x, y) point : (3, -39) represents that relationship.

So we notice that for x = 3, the related y is -39. so we can assume that there is a constant of proportionality (k) between these two numbers, such that :

y = k x

if y = -39 when x = 3, then the constant k must be -13:

-39 = (-13) (3)

then , applying this proportionality we can find what the x-value is in the incomlete pair: (x, 65):

y = -13 x

65 = -13 x

therefore x = 65/(-13) = - 65/13

and our completed pair is: (-65/13 , 65)

User Taybur Rahman
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