Integer Heronian Triangle can be Scaled so Area equals Perimeter
Jump to navigation
Jump to search
Theorem
Let $T_1$ be an integer Heronian triangle whose sides are $a$, $b$ and $c$.
Then there exists a rational number $k$ such that the Heronian triangle $T_2$ whose sides are $k a$, $k b$ and $k c$ such that the perimeter of $T$ is equal to the area of $T$.
Proof
For a given triangle $T$:
We are given that $T_1$ is an integer Heronian triangle whose sides are $a$, $b$ and $c$.
Let $\map P {T_1} = k \map \AA {T_1}$.
Let $T_2$ have sides $k a$, $k b$ and $k c$.
Then we have that:
\(\ds \map P {T_2}\) | \(=\) | \(\ds k \map P {T_1}\) | ||||||||||||
\(\ds \map A {T_2}\) | \(=\) | \(\ds k^2 \map A {T_1}\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds k \map P {T_1}\) | ||||||||||||
\(\ds \) | \(=\) | \(\ds \map P {T_2}\) |
$\blacksquare$