Curated OER
AP Exam Rubrics/ Four Color Theorem
Twelfth graders review free response questions that are present on the AP exam. In this calculus lesson, 12th graders analyze the 4 color theorem that proved 4 colors were enough to color a map while still separating adjacent countries....
Curated OER
SAS Similarity Theorem
Students identify and use the similarity theorem. In this geometry lesson, students differentiate between congruent and similar triangles. They solve problems using the computer modifying shapes by dragging.
Curated OER
The Pythagorean Theorem
Seventh graders relate the Pythagorean theorem to the real world. In this algebra lesson, 7th graders identify important properties of the Pythagorean theorem and use it to solve word problems. They create a step by step plan to help...
Curated OER
Ceva’s Theorem
Students prove and use Ceva's Theorem to solve problems. In this geometry lesson plan, students analyze polygons for patterns and calculate the area of each shape. They relate polygons to the real world.
Curated OER
Picking Pythagoras
Students discover that side measurement is used in determining angle classification of a triangle. By squaring sides, they predict whether triangles be right, obtuse, or acute. They prove the Pythagorean Theorem and use it to solve...
Curated OER
Inequalities and Triangles
Students prove and apply theorems of triangle inequality and hinge theorem. In this geometry activity, students will discuss which triangle is bigger and why. They will use theorems, such as Exterior Angle Inequality or the Pythagorean...
Curated OER
Triangle Sum Theorem
Tenth graders investigate the theorems of angles and lines to prove triagle sum theorem. In this geometry lesson, 10th graders discuss the theorems of triangles and how it is used to solve for missing sides or angles. They review how two...
Curated OER
The Proof of the Century!
Students do Web research in the field of mathematics. They explore mathematical proofs and apply them to the Pythagorean theorem. They also explore the general ideas of Fermat's Last Theorem
EngageNY
Criterion for Perpendicularity
The Pythagorean Theorem is a geometry pupil's best friend! Learners explain the equation a1b1 + a2b2 = 0 for perpendicular segments using the Pythagorean Theorem. They are able to identify perpendicular segments using their endpoints and...
EngageNY
Angle Sum of a Triangle
Prove the Angle Sum Theorem of a triangle using parallel line and transversal angle relationships. Pupils create a triangle from parallel lines and transversals. They find angle measures to show that the angles of a triangle must total...
Virginia Department of Education
Similar Triangles
Pupils work in pairs to investigate what it takes to prove that two triangles are similar. They work through various shortcuts to find which are enough to show a similarity relationship between the triangles. Small groups work with the...
Curated OER
Intermediate Value Theorem
In this Intermediate Value Theorem worksheet, students identify and explain a continuous function. They use the Intermediate Value Theorem to prove solutions of equations. This two-page worksheet contains three problems.
EngageNY
Obstacles Resolved—A Surprising Result
The greater the degree, the more solutions to find! Individuals find the real solutions from a graph and use the Fundamental Theorem of Algebra to find the remaining factors.
Geometry Accelerated
Accelerated Geometry Review Sheet
Your geometry learners use their knowledge of various geometric concepts to write proofs. Starting with givens containing parallel line segments with transversals and triangles and quadrilaterals, and the mid-point and distance formulas;...
Curated OER
Logical Relationship of Postulates & Theorems
For this postulates and theorems worksheet, students explore a concept map containing information about angles and sides, alternate interior angles, and diagonals of a parallelogram. They use the concept map to prove theorems dealing...
Curated OER
Proving the Pythagorean Theorem
Students solve problems using the pythagorean Theorem. In this geometry lesson, students complete proofs using the Pythagorean Theorem. They share their proofs and solutions with their classmates and family members.
Curated OER
Investigating AAS
Students 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 rays...
Curated OER
Exploring Characteristics Needed to Prove Two Trianlges Congruent
Tenth graders explore congruent triangles. In this geometry lesson, 10th graders investigate the conditions necessary to prove two triangles congruent. The lesson combines dry erase board activities and the use of technology.
Curated OER
Pythagorean Theorem
Eighth graders draw right triangles and identify the parts of a right triangle: right angle, interior and exterior angles, hypotenuse and legs. They predict and identify any relationships that exist between the sides of a right...
Curated OER
Proving Quadrilaterals
In this geometry worksheet, 10th graders identify the missing angles using the polygons sum conjecture. They measure exterior and interior angles using their angle theorems. There are 63 problems.
EngageNY
The Power of Algebra—Finding Pythagorean Triples
The Pythagorean Theorem makes an appearance yet again in this lesson on polynomial identities. Learners prove a method for finding Pythagorean triples by applying the difference of squares identity.
EngageNY
Unknown Angle Proofs—Proofs of Known Facts
Lead the class in a Greek history lesson with a geometric twist. Pupils relate a short video about geometric properties to modern-day methods of solving for unknown angles. They discuss parallel line theorems and complete practice...
EngageNY
Informal Proof of AA Criterion for Similarity
What does it take to show two triangles are similar? The 11th segment in a series of 16 introduces the AA Criterion for Similarity. A discussion provides an informal proof of the theorem. Exercises and problems require scholars to apply...
EngageNY
Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams
First angle measures, now segment lengths. High schoolers first measure segments formed by secants that intersect interior to a circle, secants that intersect exterior to a circle, and a secant and a tangent that intersect exterior to a...