A Pythagorean triangle is a right triangle with integer side lengths (i.e., whose side lengths 
form a Pythagorean
triple). A Pythagorean triangle with 
is known as a primitive
right triangle.
The inradius 
of a Pythagorean triangle is always a whole number since
The area of such a triangle is also a whole number since for primitive Pythagorean triples, one of 
or 
must be even, and for imprimitive triples, both 
and 
are even, so
is always a positive integer.
See also
Primitive Right Triangle, Pythagorean Triple, Right Triangle
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Cite this as:
Weisstein, Eric W. "Pythagorean Triangle." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/PythagoreanTriangle.html