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March 16th, 2016, 05:22 PM   #1
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Exclamation Don't use the rational root theorem to solve the following:

Given the following problem, how might one go about solving this without a calculator and without using the rational root theorem:

The sum of the solutions of $\displaystyle (x^2-3x)^2 - (3x^2 - 9x)=4$ is:
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March 16th, 2016, 05:38 PM   #2
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Using the substitution $u=x^2-3x$, that equation simplifies to $u^2-3u-4=0$. Can you solve it now?
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March 16th, 2016, 06:00 PM   #3
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I certainly can! Why do I never think of this stuff? It's frustrating how easy I overlook simple things like that. Thanks.
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March 16th, 2016, 06:03 PM   #4
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Originally Posted by John Travolski View Post
I certainly can! Why do I never think of this stuff? It's frustrating how easy I overlook simple things like that. Thanks.
Happens to the best of us .
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