1990 AIME Problems/Problem 4
Revision as of 19:18, 4 July 2013 by Nathan wailes (talk | contribs)
Problem
Find the positive solution to
![$\frac 1{x^2-10x-29}+\frac1{x^2-10x-45}-\frac 2{x^2-10x-69}=0$](http://latex.artofproblemsolving.com/f/a/9/fa9c9ff03c23586114f36989a00fe3362d4a8574.png)
Solution
We could clear out the denominators by multiplying, though that would be unnecessarily tedious.
To simplify the equation, substitute (the denominator of the first fraction). We can rewrite the equation as
. Multiplying out the denominators now, we get:
Simplifying, , so
. Re-substituting,
. The positive root is
.
See also
1990 AIME (Problems • Answer Key • Resources) | ||
Preceded by Problem 3 |
Followed by Problem 5 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 | ||
All AIME Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.