The simplest right triangle with rational sides (the longest side has a denominator of 45 digits!) and area 157, was found by Don Zagier in 1993.
A Paradoxical Zero-Length Hypotenuse
A strange right-triangle involving the unit imaginary number i
A curious right triangle
The sides of a pentagon, hexagon, and decagon, inscribed in congruent circles, form a right triangle.
Sangaku: Semicircle inscribed in a right triangle
Find the radius r of the semicircle inscribed in the right triangle below:
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