May 13, 2015

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

Teacher and Student versions of full lesson from engageNY

- Mathematics > General
- Mathematics > Geometry

- Grade 9
- Grade 10

Reason abstractly and quantitatively.

Construct viable arguments and critique the reasoning of others.

Use appropriate tools strategically.

Attend to precision.

Look for and make use of structure.

Use the properties of similarity transformations to establish the AA criterion for two triangles to be similar.