Free Mathematics Tutorials
Home
Math and Precalculus
Math Problems
Algebra Questions and Problems
Graphs of Functions, Equations, and Algebra
Free Math Worksheets to Download
Analytical Tutorials
Solving Equation and Inequalities
Online Math Calculators and Solvers
graphing
Free Graph Paper
Math Software
Applied Math
The Applications of Mathematics in Physics and Engineering
Antennas
Exercises de Mathematiques Utilisant les Applets
Calculus
Calculus Tutorials and Problems
Calculus Questions With Answers
Free Calculus Worksheets to Download
Free Calculus Worksheets to Download
Geometry
Geometry Tutorials and Problems
Online Geometry Calculators and Solvers
Free Geometry Worksheets to Download
Trigonometry
Trigonometry Tutorials and Problems for Self Tests
Free Trigonometry Questions with Answers
Free Trigonometry Worksheets to Download
More
Statistics
Elementary Statistics and Probability Tutorials and Problems
Mathematics pages in French
Site
About the author
Download
E-mail
Primary Math
Middle School Math
High School Math
Free Practice for SAT, ACT and Compass Math tests
Triangles
Definitions and properties of triangles in geometry.
Angles of a Triangle
A triangle is a closed plane figure with three (straight) sides.
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.
Angles B and C are equal in size.
Equilateral Triangle
A triangle with all sides equal in size.
All angles of the triangle are equal in size.
Right Triangle
A triangle with a right angle.
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
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.
Share
Tweet
Additional Info