Unit Plan
CK-12 Foundation

Ck 12: Geometry: Indirect Proof in Algebra and Geometry

For Students 9th - 10th Standards
[Free Registration/Login may be required to access all resource tools.] This concept teaches students how to write an indirect proof and provides examples of indirect proofs in Algebra and Geometry.
Unit Plan
University of Saskatchewan (Canada)

University of Saskatchewan: Techniques for Proofs

For Students 9th - 10th
The University of Saskatchewan's Department of Mathematics and Statistics provides high school students with online tutorials and exercises on what they deem some of the most important techniques for mathematical proofs: truth tables,...