MHB Solve Exponent Problem: 3^x=4^y=12^z

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To solve the equation 3^x = 4^y = 12^z, it is essential to express the relationships between the bases. By taking logarithms, one can derive that 3^(xy/(x+y)) equals 12^(zy/(x+y)). Recognizing that both 3 and 4 are factors of 12 helps simplify the problem, leading to the conclusion that z can be expressed as z = (xy)/(x+y). This relationship highlights the interconnectedness of the variables x, y, and z in the context of exponentiation. The discussion emphasizes the importance of using properties of logarithms and factor relationships to solve complex exponent problems.
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Given [Math]3^x=4^y =12^z[/Math] show that $$z=\frac{xy}{x+y}$$

I've take logs on both sides and find myself going in circles, any hints?
 
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$$3^{xy/(x+y)}=12^{zy/(x+y)}$$

Now try using the fact that $3$ and $4$ are factors of $12$ and that $4^y=3^x$.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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