Curated OER
Euclidean Direct Proofs
Learning how to prove theorems in geometry can be challenging. This resource explains what a proof is, and the different styles for proofs. It also contains links to web-based practice problems that help guide learners though example...
Curated OER
Geometric Proof and Angles
In this geometry activity, 10th graders write two-column and paragraph proofs to prove angle pair relationships. The one page activity contains five problems. Answers are not included.
Curated OER
Geometry, Measurement & Reasoning
Students construct two-column proofs. In this geometry lesson plan, students use deductive reasoning and geometric properties to justify given geometric statements. Students compare and contrast proofs.
Curated OER
More Congruent Triangles
In this congruent triangles worksheet, 10th graders solve 5 various types of geometry problems related to triangles. First, they draw and label triangles, indicating the additional pairs of corresponding parts that would have to be...
Curated OER
Inscribed Angles
For this inscribed angles worksheet, 10th graders solve 13 various types of problems related to inscribed angles in geometry. First, they identify a circle illustrated and each arc of the circle. They, students find the measure of each...
Maths Challenge
Maths challenge.net: Spider Fly Distance
A "three star geometry problem" requiring knowledge of how to complete geometric proofs and some prior math skills to figure the shortest distance between the opposite corners of a cuboid.
Maths Challenge
Maths challenge.net: Right Angle Reasoning
A geometry problem for students to use their mathematical reasoning skills to explain a right triangle property.
Oswego City School District
Regents Exam Prep Center: Writing a Proof: Direct Euclidean Proofs
This site is a look into the world of geometric proofs. You'll learn what a proof is and about the different types of proofs. Try the practice page to check your understanding. Teachers can check out the teacher resources for lesson and...
Maths Challenge
Maths challenge.net: Quadrilateral Parallelogram
A "three star geometry problem" requiring knowledge of how to complete geometric proofs and some prior math knowledge. This problem asks to prove that the mid points of any quadrilateral form a parallelogram.
Maths Challenge
Maths challenge.net: Unique Circle Equal Angles
A "three star geometry problem" - requiring the knowledge of biconditional statements and how to prove such problems.
Maths Challenge
Maths challenge.net: Odd Vertices
A "three star geometry problem" requiring knowledge of how to complete geometric proofs. The problem explains what the order of a vertex is and asks for the proof of a generalization.
Maths Challenge
Maths challenge.net: Coloured Strings
A "three star geometry problem" - requiring the knowledge of what a cuboid is and a some knowledge of how to do proofs.
Maths Challenge
Maths challenge.net: Parallelogram Property
A "three star geometry problem" requiring knowledge of how to complete geometric proofs properties of parallelogram.
Maths Challenge
Maths challenge.net: Platonic Solids
A "three star geometry problem" requiring knowledge of how to complete geometric proofs to prove that there are no more than five regular convex polyhedra.
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.
Other
Math Lab: How to Write a Good Proof
This site offers a brief description and an example of a paragraph proof. And remember, "there is never just one way of stating a proof," so others are mentioned as well.
Sophia Learning
Sophia: Types of Proofs: Lesson 3
This lesson will introduce flow chart proofs, paragraph proofs, and two-column proofs, and explain the similarity and differences between the different types of proofs. It is 3 of 5 in the series titled "Types of Proofs."