Lesson Plan

Verify experimentally that translating an angle produces an image angle with the same degree measure as the original

Verify experimentally that reflecting an angle across a line produces an image angle with the same degree measure as the original

Verify experimentally that rotating an angle about a point produces an image angle with the same degree measure as the original

Explain why angle preservation is a defining property of rigid motions and contrast this with non-rigid transformations that change angle measure

Apply the angle-preservation property to determine unknown angle measures in figures that have been transformed by a sequence of rigid motions

8.G.A.1.b

8.G.A.1: Verify experimentally the properties of rotations, reflections, and translations: 8.G.A.1.b: Angles are taken to angles of the same measure.