What is the name of this theorem.

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The discussion revolves around identifying a theorem related to a mathematical expression involving ratios and proving a specific equation. The user seeks clarity on the logical steps needed to manipulate the given expression, which involves variables a, b, c, d, e, f, and a constant k. A participant questions the accuracy of a term in the denominator, suggesting a correction that simplifies the expression. The corrected equation is deemed provable under the condition that the ratios are non-zero. The conversation emphasizes the importance of understanding the manipulation of algebraic expressions in proofs.
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Homework Statement


What is the name of this when your try to prove this... I want to know so I can search on google because this totally does not make any logical sense to me. This one does actually, however when I start having to manipulate I start getting lost...

If : a/b = c/d = e/f ; Let equal to k then: k -----> a = kb ; c = kd ; e = kf

Prove : (2a^4b^2 + 3a^2e^2 - 5e^4f) / (2b^6 + 3b^2f^2 -5k^4f^5) = a^4/b^4
 
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Miike012 said:
Prove : (2a^4b^2 + 3a^2e^2 - 5e^4f) / (2b^6 + 3b^2f^2 -5k^4f^5) = a^4/b^4
That looks wrong. Are you sure that the k^4f^5 term in the denominator on the left-hand side is correct? Getting rid of the factor of k^4 in that term yields this:

Prove : (2a^4b^2 + 3a^2e^2 - 5e^4f) / (2b^6 + 3b^2f^2 -5f^5) = a^4/b^4

This statement is provable given that a/b=c/d=e/f≠0 and assuming that the numerator and denominator on the left hand side are not zero.
 
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