40 lines
767 B
TeX
40 lines
767 B
TeX
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\documentclass[../main.tex]{subfiles}
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\begin{document}
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\problem{An Elephant and a Mosquito}
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Does the weight of an elephant equal the weight of a mosquito? Let $x$ be the weight of an elephant, and $y$ that of a mosquito.
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\begin{figure}[h]
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\centering
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\includegraphics[width=10cm]{252}
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\end{figure}
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Call the sum of the two weights $2v$, then $x + y = 2v$.
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From this equation we can obtain two more:
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\[
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x - 2v = -y \text{; } x = - y + 2v
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\]
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Multiply:
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\[
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x^2 - 2vx = y^2 - 2vy
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\]
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Add $v^2$:
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\[
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x^2 - 2vx + v^2 = y^2 - 2vy + v^2 \text{, or } (x - v)^2 = (y - v)^2
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\]
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Take square roots:
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\[
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x - v = y - v \text{; } x = y
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\]
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That is, the elephant's weight ($x$) equals the mosquito's weight ($y$). What is wrong here?
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\end{document}
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