SOLUTION: If x varies directly as y, and x = 20 when y = 5, find x when y = 9

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Question 1080750: If x varies directly as y, and x = 20 when y = 5, find x when y = 9
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

if y varies directly as x, we have
y=kx
If x+=+20 when y+=+5,we can find k:
5=20k
5%2F20=k
k=1%2F4

so, x when y=+9+ will be:
9=%281%2F4%29x
x=9%2A4
x=36