Hi

*Note: When Quantities vary directly,they are related by the relationship:

  k being  the constant of proportionality.

If y varies directly as x and y = 2 when x = 4, find x when y = 4

   y = kx

   2 = k4

   .5 = k

  y = .5x

 y/.5 = x

     x = 4/.5 = 8 when y = 4 

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