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July 31, 2014

July 31, 2014

Posted by **keeauna** on Tuesday, August 26, 2008 at 12:55am.

- math -
**drwls**, Tuesday, August 26, 2008 at 1:01amSolve this pair of equations:

x + y = 25

1/x + 1/y = 1/6

Rewrite as

1/x + 1/(25-x) = 1/6

[(25-x) + x]/[x(25-x)] = 1/6

150 = x(25-x)

x^2 -25x + 150 = 0

(x-30)(x-5) = 0

One more step

- math -
**Reiny**, Tuesday, August 26, 2008 at 7:53amI tried to finish drwls solution and verify the answers, but they would not check out.

After my second cup of coffee, I realized that my good collegue made what we used to call "wishful thinking solutions" error.

the factors would be (x-15)(x-10)

and we get symmetric solutions, that is, when x=15, y=10 and when x=10 y = 15

- math -
- math -
**drwls**, Tuesday, August 26, 2008 at 9:59amCorrect, my mistake.

- math -
**fer**, Friday, November 28, 2008 at 8:01pmx+25x+150=0

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