Line Bisector
The line bisecting a given Line Segment 
can be constructed geometrically, as illustrated above.
References
Courant, R. and Robbins, H. ``How to Bisect a Segment and Find the Center of a Circle with the Compass Alone.'' §3.4.4 in What is Mathematics?: An Elementary Approach to Ideas and Methods, 2nd ed. Oxford, England: Oxford University Press, pp. 145-146, 1996. Dixon, R. Mathographics. New York: Dover, p. 22, 1991.
- Triangle Inscribing in an Ellipse
- Triangle of Figurate Numbers
- Triangle Postulate
- Triangle Squaring
- Triangle Tiling
- Triangle Transformation Principle
- Triangular Cupola
- Triangular Dipyramid
- Triangular Graph
- Triangular Hebesphenorotunda
- Triangular Matrix
- Triangular Number
- Triangular Orthobicupola
- Triangular Pyramid
- Triangular Square Number
- Triangular Symmetry Group
- Triangulation
- Triaugmented Dodecahedron
- Triaugmented Hexagonal Prism
- Triaugmented Triangular Prism
- Triaugmented Truncated Dodecahedron
- Triaxial Ellipsoid
- Tribar
- Tribonacci Number
- Tribox