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Question 89396:  Write the inverse variation equation of the following.  Y varies inversely with x and y = 9 when x = 14.  
 Found 2 solutions by  bucky, stanbon: Answer by bucky(2189)      (Show Source): 
You can  put this solution on YOUR website! It appears as if you posted this same problem four times (postings 89393 through 89396). 
I am responding to this posting (your post number 89396) with the same answer as I  gave for 
your posting 89393, and then I am going to delete postings 89394 and 89395. Hope that works 
for you. My previous answer was: 
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The "varies inversely with x" means that as x gets bigger, y gets smaller and as x gets smaller, 
y gets bigger. 
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This relationship can be written as: 
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where k is an unknown constant. Notice that as x gets bigger, the denominator of the fraction 
on the right gets bigger, so the term on the right gets smaller. Think in terms of  x being 
10. Then make x bigger, say x = 100. k divided by 10 is bigger than k divided by 100, so 
as x gets bigger, the term k divided by x (which equals y) is getting smaller. 
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For this problem you are told that when y is 9, x is 14. So in the equation that contains 
k you can substitute 9 for y and 14 for x.  When you do that the equation becomes: 
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You can eliminate the denominator on the right side by multiplying both sides by 14 to get: 
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Multiply out the left side and the equation becomes: 
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Now you can go back to the original equation and substitute 126 for k to get the answer you 
are looking for. That answer is that the equation is: 
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You can check this by letting x = 14 and you will get: 
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So when x = 14, obviously y = 9. After that you can let x be any value (other than zero 
because division by zero is not allowed) and you can calculate the corresponding value 
for y.  Again, you can let x be two values such as 1 and 100 and you will see that as 
x gets bigger, the value of y will vary inversely because it gets smaller. 
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Hope this helps you to understand the problem better. 
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 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! Write the inverse variation equation of the following.  Y varies inversely with x and y = 9 when x = 14.  
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Equation form: y=k/x 
Need to find k if y=9 when x=14. 
9 = k/14 
k = 126 
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INVERSE VARIATION EQUATION: 
y = 126/x 
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Cheers, 
stan H. 
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