Pythagorean Triangle/Examples/3059-8580-9109

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Example of Primitive Pythagorean Triangle

The triangle whose sides are of length $3059$, $8580$ and $9109$ is a primitive Pythagorean triangle.


File:3059-8580-9109.png


It has generator $\tuple {78, 55}$.


Proof

We have:

\(\ds 78^2 - 55^2\) \(=\) \(\ds 6084 - 3025\)
\(\ds \) \(=\) \(\ds 3059\)


\(\ds 2 \times 78 \times 55\) \(=\) \(\ds 8580\)


\(\ds 78^2 + 55^2\) \(=\) \(\ds 6084 + 3025\)
\(\ds \) \(=\) \(\ds 9109\)


\(\ds 3059^2 + 8580^2\) \(=\) \(\ds 9 \, 357 \, 481 + 73 \, 616 \, 400\)
\(\ds \) \(=\) \(\ds 82 \, 973 \, 881\)
\(\ds \) \(=\) \(\ds 9109^2\)

It follows by Pythagoras's Theorem that $3059$, $8580$ and $9109$ form a Pythagorean triple.


We have that:

\(\ds 3059\) \(=\) \(\ds 7 \times 19 \times 23\)
\(\ds 8580\) \(=\) \(\ds 2^2 \times 3 \times 5 \times 11 \times 13\)

It is seen that $3059$ and $8580$ share no prime factors.

That is, $3059$ and $8580$ are coprime.

Hence, by definition, $3059$, $8580$ and $9109$ form a primitive Pythagorean triple.

The result follows by definition of a primitive Pythagorean triangle.

$\blacksquare$