Curated OER
Indirect Proof and Inequalities in one Triangle
In this geometry worksheet, 10th graders complete an indirect proof and order the sides or angles of a triangle. Also, students determine if a triangle can have sides with the given lengths. The two page worksheet contains twelve...
Curated OER
Who Dun It?
In this proofs by contradiction worksheet, students solve 1 word problem about a crime. Students use proof by contradiction to determine the criminal in the word problem.
EngageNY
The Converse of the Pythagorean Theorem
Is it a right triangle or not? Introduce scholars to the converse of the Pythagorean Theorem with a lesson that also provides a proof by contradiction of the converse. Pupils use the converse to determine whether triangles with given...
EngageNY
There is Only One Line Passing Through a Given Point with a Given Slope
Prove that an equation in slope-intercept form names only one line. At the beginning, the teacher leads the class through a proof that there is only one line passing through a given point with a given slope using contradiction. The 19th...
Curated OER
The Truth About Triangles And Proofs
High schoolers engage in a lesson that is about the classification of triangles and the mathematical proofs involved in working with them. They work on a variety of problems that are created by the teacher with the focus upon the...
EngageNY
Converse of the Pythagorean Theorem
Discover a new application of the Pythagorean Theorem. Learners prove and apply the converse of the Pythagorean Theorem in the 17th lesson in a 25-part series. The examples ask learners to verify right triangles using the converse...
Curated OER
Indirect Euclidean Proofs
For this indirect Euclidean proof worksheet, students write statements supporting the reasons for a given proof. This one-page worksheet contains ten problems.
Curated OER
Indirect Euclidean Proofs
In this Euclidean proofs activity, 10th graders solve 10 different problems that include completing indirect Euclidean proofs. First, they write a statement for each of the reasons listed on the sheet of proofs. Then, students solve the...
CK-12 Foundation
Limit of a Sequence: Finding the Limit of a Sequence (Part 2)
What does it mean if young mathematicians cannot put the squeeze on a sequence? Learners investigate a divergent sequence and find the formula for the nth term. Using the definition of a limit of a sequence, pupils try to find the limit...
Curated OER
Three for the Money: The Degree/Diameter Problem
Students explore the concept of vertex-edge graphs. In this vertex-edge graphs lesson, students try to construct a graph with a given diameter, number of vertices, size, and planarity. Students construct various vertex-edge...
Curated OER
Complex Analysis: Theorems Following Cauchy's Integral Formulas
In this integral formula, students explore how theorems are derived. They write proofs supporting Cauchy's Inequality, Liouville's Theorem, the Fundamental Theorem of Algebra, Gauss' Mean Value Theorem and Cauchy's Residue Theorem. ...
Illustrative Mathematics
Applying the Pythagorean Theorem in a Mathematical Context
Participants who use this resource will apply the Pythagorean Theorem to show whether or not the shaded triangle inscribed in a rectangle is a right triangle. Once all of the sides on the shaded triangle are found, it is important that...
Curated OER
Investigating AAS
Young scholars investigate the theorems of ASA, AAS, AAA and ASA. In this geometry lesson, students discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two angles are formed by two...
Curated OER
Babylonian Mathematics 2
Students research Babylonian mathematics. They calculate simple surd numbers. Students find the fractional form of rational numbers expressed as decimals. They work with numbers in base 60.
Curated OER
Properties of Geometry
In this properties of geometry activity, 10th graders solve and complete 12 different problems that include various theorems. First, they draw a figure that illustrates the SAS inequality property. Then, students prove that two line...
Oswego City School District
Regents Exam Prep Center: Indirect Euclidean Proofs
This Oswego City School District Regents Exam Prep site shows you how to proof something by showing that it is false. This look at indirect proofs includes a practice and a teacher resource page, which features a warm-up activity.
Other
Platonic Realms: Conic Sections
A proof to show that the square root of two is an irrational number, followed by a shorter and even more beautiful proof.