ASS Theorem
Specifying two adjacent side lengths 
and 
of a Triangle (taking 
) and one AcuteAngle 
opposite does not, in general, uniquely determine a triangle. If 
, there are two possibleTriangles satisfying the given conditions. If 
, there is one possible Triangle. If
, there are no possible Triangles. Remember: don't try to prove congruence with the ASStheorem or you will make make an ASS out of yourself.
- Apothem
- Apparatus Function
- Appell Hypergeometric Function
- Appell Polynomial
- Appell Transformation
- Apple
- Approximately Equal
- Approximation Theory
- Apéry's Constant
- Arakelov Theory
- Arbelos
- Arborescence
- Arboricity
- Arc
- Arch
- Archimedean Solid
- Archimedean Solid Stellation
- Archimedean Spiral
- Archimedean Spiral Inverse Curve
- Archimedean Valuation
- Archimedes Algorithm
- Archimedes' Axiom
- Archimedes' Cattle Problem
- Archimedes' Circles
- Archimedes' Constant