Reckoning / Shape / Right triangle
Plane figure · Triangles
Right triangle
One angle is 90°. The side opposite it, the hypotenuse, is the longest.
Dimensions
Results
area A
hypotenuse c
Formulas
Two copies make an a by b rectangle. The hypotenuse follows from Pythagoras’ theorem, which this triangle is the picture of.
Checked: the A formula agrees with a Monte Carlo measurement of the shape itself, made from its geometric definition, every time the site is built.
Topology lens
Topologically a disc, like every figure here without a hole: Euler characteristic 1. Stretching turns it into a circle, a square or a star. More on the lens.