Lesson Plan

State the formal definition of congruence in terms of rigid motions: two figures are congruent if and only if there exists a sequence of rigid motions (translations, reflections, rotations) that maps one figure exactly onto the other

Predict the effect of a given rigid motion on a given figure, including the positions of all vertices and the orientation of the image

Apply a sequence of rigid motions to transform a figure and verify that the image coincides with a target figure

Determine whether two given figures are congruent by finding a rigid motion (or sequence of rigid motions) that maps one onto the other, or by arguing that no such rigid motion exists

Explain why the rigid-motion definition of congruence is equivalent to the intuitive notion of "same shape and size"

HSG.CO.B.6

HSG.CO.B.6: Use geometric descriptions of rigid motions to transform figures and to predict the effect of a given rigid motion on a given figure; given two figures, use the definition of congruence in terms of rigid motions to decide if they are congruent.