CK-12 Foundation
Ck 12: Triangle Sum Theorem
[Free Registration/Login Required] Students explore the concept of the triangle sum theorem by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more...
CK-12 Foundation
Ck 12: Triangle Sum Theorem
[Free Registration/Login Required] Students explore the concept of the triangle sum theorem by navigating through the interactive learning module and then answering questions that go along with the module. Students can also learn more...
CK-12 Foundation
Ck 12: Geometry: Triangle Sum Theorem Grades 9 10
[Free Registration/Login may be required to access all resource tools.] This concept teaches students the Triangle Sum Theorem, and how to use it.
CK-12 Foundation
Ck 12: Geometry: Triangle Sum Theorem Grade 7
[Free Registration/Login may be required to access all resource tools.] Recognize the sum of the interior angles of a triangle as 180 degrees.
CK-12 Foundation
Ck 12: Geometry: Triangle Sum Theorem Grades 8 10
[Free Registration/Login may be required to access all resource tools.] Recognize the sum of the interior angles of a triangle as 180 degrees.
CK-12 Foundation
Ck 12: Geometry: Triangle Sum Theorem Grade 8
[Free Registration/Login may be required to access all resource tools.] Finding and understanding the angle measures of triangles.
Texas Instruments
Texas Instruments: Exterior and Interior Angle Theorem
In this activity, students investigate the relationship between the exterior angle of a triangle and its remote interior angles. They study the Triangle Sum Theorem and the Exterior Angle Theorem.
Texas Instruments
Texas Instruments: Triangle Sum
This activity is used to discover that the sum of the measures of the triangle angles is constant and to discover ways of proving the theorem listed in the activity.
CK-12 Foundation
Ck 12: Geometry: Comparing Angles and Sides in Triangles
[Free Registration/Login may be required to access all resource tools.] This concept teaches students the relationship between opposite angles and sides in triangles and how to use this relationship to compare triangles. students examine...
Government of Alberta
Learn Alberta: Math Interactives: Exploring Angles Within a Triangle
This multimedia Learn Alberta math resource looks at angles of a triangle in the context of building bikes and choosing bike sizes. The accompanying interactive component lets students explore build different sized triangles while...
Texas Instruments
Texas Instruments: Sum of Remote Interior Angles Equals Exterior Angle
Draw a triangle with exterior angle. Measure the exterior angle and each remote interior angle. Use the Alpha hand to check that the sum of the remote interior angles is always equal to the exterior angle.
CK-12 Foundation
Ck 12: Geometry: Third Angle Theorem Grades 8 10
[Free Registration/Login may be required to access all resource tools.] Apply the Third Angle Theorem.
Texas Instruments
Texas Instruments: Measuring Angles in a Triangle
In this activity, students learn about the sum of the angles in a triangle. They understand triangles and their interior angles.
Oswego City School District
Regents Exam Prep Center: Angles and Triangles
On this site a viewer can learn about the different types of triangles, and categorized by either angles or sides. Tutorials are also included for interior and exterior angles of triangles. A teacher resource page includes a lesson plan...
Walter Fendt
Walter Fendt: Sum of Angles in a Triangle
A short interactive activity to show that the sum of the angles of a triangle is 180 degrees.
Texas Education Agency
Texas Gateway: Making and Verifying Conjectures About Triangles
Given examples of triangles and their component parts, the student will use explorations and concrete models to verify and apply the and find the sum of interior angles.
CK-12 Foundation
Ck 12: Elem Math: Determine Unknown Angles: Isosceles, Scalene, Right Triangles
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on finding the missing angles in triangles.
CK-12 Foundation
Ck 12: Elem Math: Determining the Unknown Angle in a Triangle
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on how to determine a missing angle in a triangle.
CK-12 Foundation
Ck 12: Geometry: Angle Measures in Given Triangles
[Free Registration/Login may be required to access all resource tools.] Find the degree measure of an unknown angle in given triangles.
CK-12 Foundation
Ck 12: Elem Math: Determining the Unknown Angle in a Right Triangle
[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on finding a missing angle in a right triangle.
CK-12 Foundation
Ck 12: Geometry: Exterior Angles Theorems
[Free Registration/Login may be required to access all resource tools.] This concept teaches students the sum of exterior angles for any polygon and the relationship between exterior angles and remote interior angles in a triangle....
Khan Academy
Khan Academy: Find Angles in Triangles
Find missing angle measures using the properties of triangles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or receive hints.
Math Is Fun
Math Is Fun: Interior Angles of Polygons
Learn what an interior angle of a polygon is and how you can calculate their value in triangles, quadrilaterals, and pentagons. Includes a chart that overviews the "general rule" for determining the sum of internal angles in any polygon...
Texas Instruments
Texas Instruments: Properties of the Centers of a Triangle
Students investigate the sum of the measures of the interior angles of a triangle. This activity explores interior angles, and their relationship with the exterior angles of a triangle [Requires Adobe Reader.]