Three Equations, Three Unknowns.

Thread starter ƒ(x) → ∞
Start date Mar 7, 2010
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AI Thread Summary

The discussion revolves around solving three equations with three unknowns: 5xy/(x+y) = 6, 7yz/(y+z) = 10, and 8zx/(z+x) = 15. Participants note that the equations appear complex but suggest that inverting them might simplify the problem. There is a consensus that while cross-multiplying and eliminating variables is a possible method, it may not be the most efficient approach. The challenge lies in recognizing the potential for a simpler solution through manipulation of the equations. Overall, the thread emphasizes the need for creative problem-solving strategies in tackling these types of equations.

Mar 7, 2010

ƒ(x) → ∞

Homework Statement

But somehow not that simple..

\frac{5xy}{x+y} =6\left.

\frac{7yz}{y+z} =10\left.

\frac{8zx}{z+x} =15\left.

Homework Equations

The Attempt at a Solution

Tried and failed.

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Mar 7, 2010

epenguin

Science Advisor

Looks like if you turned the equations upside down you have something easy to solve.

I think they want you to see that, although you could no doubt slog it out by cross multiplying and eliminating.

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