Math Open Reference
Math Open Reference: Interior Angles of a Polygon
Learn about interior angles of a polygon with this handy reference guide. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
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...
Sophia Learning
Sophia: Sum of Angles in Polygons
This tutorial with video and slideshow components investigate the characteristics of polygons as well as how to calculate the interior and exterior angles of any polygon. It offers two PowerPoint presentations and two videos that feature...
Oswego City School District
Regents Exam Prep Center: Polygons: Interior and Exterior Angles
A great resource where you can learn how to calculate the measures of the interior and exterior angles of any regular polygon with these tutorials. There are several practice pages for someone to try. The teacher resource page includes...
Texas Education Agency
Texas Gateway: Making Conjectures About Other Polygons
Given information about the properties of polygons, students will verify theorems about the relationships, including the sum of interior angles, and apply these relationships to solve problems.
Texas Education Agency
Texas Gateway: Geometric Properties of Angle Relationships in Polygons
Given numerical and/or geometric patterns that represent geometric properties of angle relationships in polygons, the student will investigate patterns to make conjectures about interior and exterior angles of polygons.
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: 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.
Illustrative Mathematics
Illustrative Mathematics: 8.g.a Triangle's Interior Angles
In this task, 8th graders are presented with a drawing of two parallel lines with a triangle touching them at all three of its vertices. They are asked to prove that the sum of the triangles' angles equals 180 degrees. Aligns with 8.G.A.5.
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.
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...
CK-12 Foundation
Ck 12: Geometry: Interior Angles in Convex Polygons
[Free Registration/Login may be required to access all resource tools.] Find the sum of the interior angles of a convex polygon.
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....
CK-12 Foundation
Ck 12: Geometry: Interior Angles in Convex Polygons
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to calculate the sum of the interior angles of a polygon and the measure of one interior angle of a regular polygon.
Texas Instruments
Texas Instruments: Measuring Angles in a Quadrilateral
In this activity, use an interactive, and investigative approach to determining the sum of the interior angles of a quadrilateral. They use Cabri Jr. to draw, measure, and calculate the characteristics of the angles of quadrilaterals.
Texas Instruments
Texas Instruments: Investigating the Angle Sum Theorem of Polygons
This activity will allow students to use Cabri Jr. to find the sum of the measures of interior angles of convex polygons and visually see how the Interior Angle Sum Theorem works.
Texas Instruments
Texas Instruments: Angles in a Polygon
Students will expore the interior and exterior angle of 3 polygons and develop the formula to calculate the sum of degrees without the measurement of the angles being taken.
Mangahigh
Mangahigh: Shape: Interior Angles of Polygons
Determine the sum of the interior angles of polygons.
Khan Academy
Khan Academy: Angles of a Polygon
Find the sum of interior angles of different polygons.
National Council of Teachers of Mathematics
Nctm: Illuminations: Angle Sums
Students may use this computer applet to explore angle sums of triangle, quadrilaterals, pentagons and hexagons.
Texas Instruments
Texas Instruments: Angles of a Triangle
In this activity, students investigate the sum of the measures of the interior angles of a triangle. They will explore interior angles, and their relationship with the exterior angles of a triangle.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Angle Sum Theorem
Find a quick, concise explanation of the Angle Sum Theorem. A step by step explanation of the proof is included to help you understand the theorem.
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...
Sophia Learning
Sophia: Triangle Interior Angles Practice: Lesson 5
This lesson provides practice problems that involve the sum of the interior angles of triangles. It is 5 of 6 in the series titled "Triangle Interior Angles Practice."