**Title:** Angles, Angles, and More Angles

**Description:**
This lesson is designed to develop knowledge about the angles of a triangle. This lesson will prove that the interior angles of a triangle will have a sum of 180 degrees. This lesson will prove that an exterior angle is the sum of the remote interior angles. This lesson will show the relationships of the angles of parallel lines and transversals.
This lesson results from the ALEX Resource Gap Project.
**Standard(s): **

[MA2015] (8) 20: Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angle-angle criterion for similarity of triangles. [8-G5]

**Subject:**Mathematics (8)

**Title:**Angles, Angles, and More Angles

**Description:**This lesson is designed to develop knowledge about the angles of a triangle. This lesson will prove that the interior angles of a triangle will have a sum of 180 degrees. This lesson will prove that an exterior angle is the sum of the remote interior angles. This lesson will show the relationships of the angles of parallel lines and transversals. This lesson results from the ALEX Resource Gap Project.

**Title:** Angle Sums

**Description:**
In this student interactive, from Illuminations, students explore the sum of the interior angles of triangles, quadrilaterals and other polygons. They can select which type of shape to explore; and, for triangles and quadrilaterals, they can watch a visual demonstration
**Standard(s): **

[MA2015] (8) 20: Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angle-angle criterion for similarity of triangles. [8-G5]

**Subject:**Mathematics

**Title:**Angle Sums

**Description:**In this student interactive, from Illuminations, students explore the sum of the interior angles of triangles, quadrilaterals and other polygons. They can select which type of shape to explore; and, for triangles and quadrilaterals, they can watch a visual demonstration

**Thinkfinity Partner:**Illuminations

**Grade Span:**6,7,8