# Category:Triangles

This category contains results about Triangles in the context of Geometry.

Definitions specific to this category can be found in Definitions/Triangles.

## Subcategories

This category has the following 18 subcategories, out of 18 total.

### A

### C

### E

### I

### L

### M

### O

### P

### R

### S

## Pages in category "Triangles"

The following 81 pages are in this category, out of 81 total.

### A

### C

- Circumscribing about Circle Triangle Equiangular with Given
- Circumscribing Circle about Triangle
- Congruence of Triangles is Equivalence Relation
- Construction of Parallelogram equal to Triangle in Given Angle
- Construction of Parallelogram on Given Line equal to Triangle in Given Angle
- Construction of Triangle from Given Lengths
- Converse Hinge Theorem
- Crossbar Theorem

### E

- Equal Sized Triangles on Equal Base have Same Height
- Equal Sized Triangles on Same Base have Same Height
- Equiangular Triangles are Similar
- Euler Triangle Formula
- Euler Triangle Formula/Lemma
- External Angle of Triangle equals Sum of other Internal Angles
- External Angle of Triangle Greater than Internal Opposite

### G

### L

- Law of Cosines
- Law of Sines
- Law of Tangents
- Length of Angle Bisector
- Length of Circumradius of Triangle
- Length of Inradius of Triangle
- Line Parallel to Side of Triangle which Bisects One Side also Bisects Other Side
- Lines Through Endpoints of One Side of Triangle to Point Inside Triangle is Less than Sum of Other Sides
- Lines Through Endpoints of One Side of Triangle to Point Inside Triangle is Less than Sum of Other Sides/Corollary

### P

### R

### S

- SAA
- SAS
- Sides of Equiangular Triangles are Reciprocally Proportional
- Similar Figures on Sides of Right-Angled Triangle
- Similar Polygons are composed of Similar Triangles
- Similar Polygons are composed of Similar Triangles/Porism
- Sine of Angle of Triangle by Semiperimeter
- Square equals Sum of Squares implies Right Triangle
- SSS
- Steiner-Lehmus Theorem
- Stewart's Theorem
- Sum of Angles of Triangle equals Two Right Angles
- Sum of Two Sides of Triangle Greater than Third Side

### T

- Triangle Angle-Side-Angle and Side-Angle-Angle Equality
- Triangle Angle-Side-Angle and Side-Angle-Angle Equality/Proof
- Triangle Angle-Side-Angle Equality
- Triangle Equality
- Triangle Side-Angle-Angle Equality
- Triangle Side-Angle-Side Equality
- Triangle Side-Side-Side Equality
- Triangles with Equal Base and Same Height have Equal Area
- Triangles with Integer Area and Integer Sides in Arithmetical Progression
- Triangles with One Equal Angle and Two Other Sides Proportional are Similar
- Triangles with One Equal Angle and Two Sides Proportional are Similar
- Triangles with Proportional Sides are Similar
- Triangles with Same Base and Same Height have Equal Area
- Triangles with Two Equal Angles are Similar
- Triangles with Two Sides Parallel and Equal
- Two Angles of Triangle Less than Two Right Angles