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 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: Measuring Polygons an Introduction to Cabri Jr.
This activity is designed as an introduction to using the Carbri Jr. application on the TI-83+/84+ calculators. Students are guided through the menu system and are shown how to draw triangles, quadrilaterals and and a pentagon. Perimeter...
CK-12 Foundation
Ck 12: Elem Math: Determining Unknown Angles in Parallelograms
[Free Registration/Login may be required to access all resource tools.] Students watch a video and attempt practice problems on how to determine missing angles in a parallelogram.
CK-12 Foundation
Ck 12: Elem Math: Determining Unknown Angles in Trapezoids
[Free Registration/Login may be required to access all resource tools.] Students watch a video overview and attempt practice problems on finding the missing angles in a trapezoid.
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....
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.
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.
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.
Varsity Tutors
Varsity Tutors: Hotmath: Exterior Angles
This interactive tool has student explore the topic of exterior angles of a polygon. The tool allows learners to change the number of sides to find the sum of the exterior angles of a variety of polygons.