Undergrad Exponential equation with logs

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The discussion revolves around solving the equation involving logarithms and exponential terms, specifically $$\log_{10}\big[25^{x+1}+4^{x+1}-19\cdot 10^x\big]=\log_{10}\big[10^{x+1}\big]$$. Participants note that the equation can be simplified to $$25^{x+1}+4^{x+1}=\frac{29}{10}\cdot 10^{x+1}$$, leading to solutions of x=0 and x=-2. There is a consensus that the problem lacks a straightforward solution method. The conversation highlights the importance of recognizing common factors and algebraic manipulation in reaching the answers. Overall, the key solutions identified are x=0 and x=-2.
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How can i continue from here, answer is x=0,-2

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You lost a factor 4 for 2x 2x.

I would make some common factors of 10x and from there on say that you can see the solution. There is no nice way to solve this as far as I can see.
 
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mfb said:
You lost a factor 4 for 2x 2x.

I would make some common factors of 10x and from there on say that you can see the solution. There is no nice way to solve this as far as I can see.
You mean write down 25 as 10log1025?
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dont mind the t=0, since it cannot be.
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Answers are x=0, x=-1.
Anyone have a clue how to show it ? it doesn't have to be a proof.
 
Dank2 said:
Answers are x=0, x=-1.
Anyone have a clue how to show it ? it doesn't have to be a proof.
If the equation is:
$$\log_{10}\big[25^{x+1}+4^{x+1}-19\cdot 10^x\big]=\log_{10}\big[10^{x+1}\big]$$,
then with some algebra, you can reduce it down to:
$$
25^{x+1}+4^{x+1}=\frac{29}{10}\cdot 10^{x+1}
$$
and can easily see ##x=0## is a solution and if you plug in ##x=-2##, confirm -2 is a solution also.
 
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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