SOLUTION: How do you find the averages of polynomials such as in this problem: If {{{1/x+1/y=1/z}}} and xy=z , what is the average of x and y?
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Question 86009This question is from textbook Barron's PSAT/NMSQT 2006/2007
: How do you find the averages of polynomials such as in this problem: If and xy=z , what is the average of x and y?
This question is from textbook Barron's PSAT/NMSQT 2006/2007
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
1/x+1/y=1/z and xy=z
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Add the left side of the equation to get:
(y+x)/xy = 1/z
Substitute z in place of xy to get:
(y+x)/z = 1/z
The numerators must be equal:
x+y=1
To get the average divide by 2:
(x+y)/2 = 1/2
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Cheers,
Stan H.
Cheers,
Stan H.
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