Additional Info

Share

Triangles

Definitions and properties of triangles in geometry.

Angles of a Triangle

A triangle is a closed plane figure with three (straight) sides.

Triangle


The sum of all three interior angles of a triangle is equal to 180 degrees.

Isosceles Triangle

A triangle with two sides equal in size.
Isosceles Triangle
Angles B and C are equal in size.

Equilateral Triangle

A triangle with all sides equal in size.
Equilateral Triangle
All angles of the triangle are equal in size.

Right Triangle

A triangle with a right angle.
Right Triangle

c is the hypotenuse, a and b are the legs of the triangle.

Pythagorean theorem:

c 2 = a 2 + b 2

Sine law in a Triangle

Triangle without right angle may be solved using sine law expressed as follows
Right Triangle


a / sin(A) = b / sin(B) = c / sin(C)

Cosine law in a Triangle

cosine law expressed as follows

a 2 = b 2 + c 2 - 2 b c cos(A)

or b 2 = a 2 + c 2 - 2 a c cos(B)

or c 2 = b 2 + a 2 - 2 b a cos(C)

More geometry references
Triangle Problems

Geometry Tutorials, Problems and Interactive Applets.



Home Page -- HTML5 Math Applets for Mobile Learning -- Math Formulas for Mobile Learning -- Algebra Questions -- Math Worksheets -- Free Compass Math tests Practice
Free Practice for SAT, ACT Math tests -- GRE practice -- GMAT practice Precalculus Tutorials -- Precalculus Questions and Problems -- Precalculus Applets -- Equations, Systems and Inequalities -- Online Calculators -- Graphing -- Trigonometry -- Trigonometry Worsheets -- Geometry Tutorials -- Geometry Calculators -- Geometry Worksheets -- Calculus Tutorials -- Calculus Questions -- Calculus Worksheets -- Applied Math -- Antennas -- Math Software -- Elementary Statistics High School Math -- Middle School Math -- Primary Math
Math Videos From Analyzemath
Author - e-mail


Updated: 2 April 2013

Copyright 2003 - 2014 - All rights reserved