SOLUTION: If y varies directly as x, and y = 7 when x =5, find y when x =10 y= blank?

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Question 696078: If y varies directly as x, and y = 7 when x =5, find y when x =10
y= blank?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
If y varies directly as x, and y = 7 when x =5, find y when x =10
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y = k*x
7 = k*5
k = 7/5 = 1.4
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@ x = 10:
y = 1.4*10
y = 14
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Or using proportions:
y = k*x
y/x = k (a constant)
7/5 = k = y/10
7/5 = y/10
5y = 70
y = 14