Isosceles Triangle
A Triangle with two equal sides (and two equal Angles). The name derives from the Greek iso (same)and skelos (Leg). The height of the above isosceles triangle can be found from the Pythagorean Theorem as
 | (1) |
 | (2) |
There is a surprisingly simple relationship between the Area and Vertex Angle 
. As shown in theabove diagram, simple Trigonometry gives
 |  |  | (3) |
 | |  | (4) |
so the Area is
 | (5) |
No set of 
points in the Plane can determine only Isosceles Triangles.
- Laplace's Integral
- Laplace-Stieltjes Transform
- Laplace Transform
- Laplacian
- Laplacian Determinant Expansion by Minors
- Large Number
- Large Prime
- Laspeyres' Index
- Latin Cross
- Latin-Graeco Square
- Latin Rectangle
- Latin Square
- Latitude
- Lattice
- Lattice Algebraic System
- Lattice Animal
- Lattice Distribution
- Lattice Graph
- Lattice Groups
- Lattice Path
- Lattice Point
- Lattice Reduction
- Lattice Sum
- Lattice Theory
- Latus Rectum