Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Logic and Proof Exercises
Twenty-five problems cover the topic of logic and proof in different geometry settings. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View Solution"...
Varsity Tutors
Varsity Tutors: Hotmath: Graphing Calculator Practice Problems: Logic and Proof
Practice using your graphing calculator for logic and proof problems. If you get stumped or if you would like to check your work, then select the View Solution button, which is located directly under each problem.
McGraw Hill
Glencoe Mathematics: Self Check Quiz on Reasoning & Proof
The online assessment demonstrates knowledge of concepts utilized in Geometry. The multiple choice questions test students on mathematical reasoning and proof.
Hopelink
Hopelink: Math Lesson Idea: Word Problems
Teach your young scholars to reason with language and to use imagery to translate language into mathematical equations.
Oswego City School District
Regents Exam Prep Center: Styles of Proof
Find out the general form for two column proofs, flow proofs, and paragraph proofs here. The site is very brief and discusses each type of proof using the same example.
TED Talks
Ted: Ted Ed: How Many Ways Are There to Prove the Pythagorean Theorem?
Betty Fei details these three famous Pythagorean theorem proofs.
CK-12 Foundation
Ck 12: Analysis: Inductive Proofs
[Free Registration/Login may be required to access all resource tools.] Introduction to proofs of series sums by induction. Students examine guided notes, review guided practice, watch instructional videos and attempt practice problems.
Math Planet
Math Planet: Geometry: Conjecture
Conjecture is explained through examples and a video lesson. [0:41]
CK-12 Foundation
Ck 12: Geometry: Deductive Reasoning
[Free Registration/Login may be required to access all resource tools.] This concept introduces students to deductive reasoning using the laws of detachment, contrapositive, and syllogism. Students examine guided notes, review guided...
CK-12 Foundation
Ck 12: Geometry: Conjectures and Counterexamples
[Free Registration/Login may be required to access all resource tools.] In this lesson students make conjectures and provide counterexamples. Students examine guided notes, review guided practice, watch instructional videos and attempt...
National Council of Teachers of Mathematics
Nctm: Illuminations: Proof Without Words: Pythagorean Theorem
This applet proves the Pythagorean Theorem "without words" using geometry.
CK-12 Foundation
Ck 12: 3.3 Inverse Functions
This section explores the process for finding inverses of functions, and then proving the function and its inverse algebraically. Additionally, it explores how the graphs of functions and their inverses compare to each other, and it...
Maths Challenge
Maths challenge.net: Christmas Trees
Find how many Christmas trees can be planted using your conversion and geometric knowledge.
Maths Challenge
Maths challenge.net: Cables
This is a proof problem, considered a "three star" geometry problem requiring knowledge of proofs and properties of circles to solve this problem with cables in duct problem.
Maths Challenge
Maths challenge.net: Radical Axis
This is a "three star" geometry problem requiring knowledge of proofs and properties of circles. Students will use the given definition of radical axis and prior knowledges to prove a way to find a radical axis.
Cut the Knot
Cut the Knot!: The Law of Cosines (Cosine Rule)
This site from Cut The Knot provides an overview of the law of cosines, complete with an explanation of the law and a proof of the law.
Sophia Learning
Sophia: Cpctc: Lesson 2
This lesson will demonstrate the use of CPCTC in triangle congruencey proofs. It is 2 of 4 in the series titled "CPCTC."
ClassFlow
Class Flow: Circles Geometry
[Free Registration/Login Required] Students identify segments and lines related to circles and the properties of a tangent to a circle.
Wolfram Research
Wolfram Mathworld: Theorem
This simple MathWorld site defines theorems and briefly explains how a theorem is produced.
Wolfram Research
Wolfram Math World: Conjecture
This MathWorld site gives the definition of conjecture with links to related sites.
Michigan State University
Michigan State University: Biometrics: Hand Geometry
Students use hand geometry to prove their own identification.