Analyze Math
Analyze Math: Area of Triangles
The geometry resource explores the different formulas used to calculate the area of triangles. The applet investigates the angles and sides of a triangle.
Other
Visnos: Polygons
Create regular and irregular polygons and determine the angles and side lengths with this interactive exercise. Use Safari or Chrome browser.
Math Planet
Math Planet: Pre Algebra: Triangles
Learn about the types of triangles by taking a look at an example and a video lesson.
Khan Academy
Khan Academy: Area of Triangles
Practice finding the area of right, acute, and obtuse triangles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Mathigon
Mathigon: Geometry: Angles and Polygons: Drawing Triangles
This lesson focuses on the Triangle Inequality, when the sum of the lengths of any two sides of a triangle is greater than the length of the third. When this happens, the three sides cannot form a triangle.
Khan Academy
Khan Academy: Triangle Side Length Rules
Practice solving problems with triangle side length rules.
Khan Academy
Khan Academy: Constructing Triangles
Practice constructing triangles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Math Open Reference
Math Open Reference: Triangles
A complete reference guide to types of triangles and triangle perimeter and area. It provides definitions and interactive animated activities that enhance further explanation.
National Council of Teachers of Mathematics
Nctm: Illuminations: Isosceles Triangle Area
Explore when an isosceles triangle obtains its maximum area.
National Council of Teachers of Mathematics
Nctm: Illuminations: Area of Triangles
To find the area of a triangle, try to make a parallelogram using a copy of the triangle.
Geometry Help
Geometry Help: Equilateral Triangles
Explains the basic concept of equilateral triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
Geometry Help
Geometry Help: Triangles
Explains the basic concept of triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.
OER Commons
Oer Commons: Exploring the Properties of a Triangle
In this activity, students explore properties of triangles. They fold paper to make a triangle and measure its angles. Students also draw triangles with given conditions. Included are examples, discussion questions, and closing activities.
OER Commons
Oer Commons: Classifying Triangles
For this lesson, students learn to classify triangles by the size of the angles and the measures of the sides. Students will use interactives to explore equilateral, isosceles, scalene, acute, obtuse, and right triangles. Included are...
Quia
Ixl Learning: Area of Triangles
Brush up on your math skills relating to the area of triangles then try some practice problems to test your understanding.
PBS
Pbs Learning Media: Triangles: Targeted Math Instruction
Students will learn how to apply the properties and characteristics of all triangles to solve real-world problems and identify and use the unique characteristics of right, isosceles, equilateral, acute, obtuse, and scalene triangles.
AAA Math
Aaa Math: Finding the Third Angle of a Triangle
Finding the third angle of a triangle becomes easier by the explanation and examples presented.
The Math League
The Math League: Scalene Triangle
This site provides the definition of Scalene triangles.
Other
Mathematics Internet Library: Free Internet Books
Practice problem worksheets are available for students needing to study basic terms relating to triangles and other math concepts.
Other
Ic Teachers: Shapes: Triangles
Are you looking for a very basic website that will explain the basic properties of a triangle? Use this site to learn about the properties of equilateral triangles, isosceles triangles, right triangles,and scalene triangles. There are...
ClassFlow
Class Flow: Triangles
[Free Registration/Login Required] Using this flipchart students learn to recognize and classify different triangles, including equilateral, isosceles and scalene. The teacher will use this lesson plan to review different types of...
Free Math Help
Free Math Help: Congruent Triangles
Students learn about congruent triangles. The tutorial consists of definitions and sample exercises with solutions.