Students will prove the angle-angle criterion for two triangles to be similar and use it to solve triangle problems.

CK-12 Foundation's Geometry FlexBook is a clear presentation of the essentials of geometry for the high school student. Topics include: Proof, Congruent Triangles, Quadrilaterals, Similarity, Perimeter & Area, Volume, and Transformations.

Students prove the angle-angle criterion for two triangles to be similar and use it to solve triangle problems.

Students prove the side-angle-side criterion for two triangles to be similar and use it to solve triangle problems.
Students prove the side-side-side criterion for two triangles to be similar and use it to solve triangle problems.

This is a PBL project that asked students to select a select a major period/style of architecture in history, research it to see how this genre influenced the major architectural design elements, and then synthesize the information as part of a redesigned college campus. The final designs are presented to working architects and used as a basis to prove key geometry standards in the Math 2 curriculum.

Students will know an informal proof of the angle-angle (AA) criterion for similar triangles and students will present informal arguments as to whether or not triangles are similar based on the AA criterion.

This task works toward establishing the AA criterion for similarity of triangles by providing a detailed sequence of transformations that moves one of the given triangles to the other.

In this activity, students will use properties of similarity transformations to establish the AA criterion for two triangles.