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Pythagorean Theorem

Relationship between the sides of right triangles using the formula a² + b² = c². Guides students through solving for missing side lengths and applying the theorem to real-world geometric problems.

MathNumbers & CountingCounting ObjectsNumber NamesComparing NumbersNumber OperationsCounting SequenceNumbers 0-10Place Value Understanding and SystemAdd and Subtract Within 20Addition and Subtraction ConceptsAddition and Subtraction EquationsAddition and Subtraction ProblemsFoundations for MultiplicationMultiplication and Division PropertiesMultiply and Divide Within 100Multiplication and Division ProblemsFactors and MultiplesProperties of OperationsPatterns and RelationshipsGenerate and Analyze PatternsMulti-Digit ArithmeticPlace Value OperationsMulti-Digit and Decimal OperationsNumerical ExpressionsFour Operations and PatternsFour Operations Problem SolvingMeasurement & DataMeasurable AttributesMeasuring LengthsMeasure and Estimate Lengths in Standard UnitsRelate Addition and Subtraction to LengthClassifying and Counting ObjectsTime and MoneyArea Concepts and MeasurementPerimeter and Area MeasuresAngle Concepts and MeasurementTime, Volume, and MassMeasurement Unit ConversionsGeometryIdentifying ShapesShapes and AttributesShape Attributes and ReasoningShapes and CompositionClassifying 2D FiguresGeometric Figures and RelationshipsLines, Angles, and ShapesAngle, Area, and VolumeGeometric MeasurementVolume of 3D ShapesCoordinate Plane ApplicationsTransformations in the PlaneCongruence and SimilarityUnderstand congruence in terms of rigid motionsSimilarity and TransformationsProve Theorems Involving SimilarityPythagorean TheoremTrigonometry for General TrianglesMake Geometric ConstructionsProve Geometric TheoremsTheorems About CirclesFind Arc Lengths And Areas of Sectors of CirclesVolume FormulasRelationships Between Two-Dimensional and Three-Dimensional ObjectsProve Simple Geometric Theorems AlgebraicallyTranslate Between Geometric Description and Equation for Conic SectionApply Geometric Concepts in Modeling SituationsFractions & DecimalsFractions as NumbersBuilding FractionsFraction Equivalence and OrderingAdding and Subtracting FractionsMultiplying and Dividing FractionsDividing FractionsDecimal FractionsMulti-Digit Computation and FactorsAdd, Subtract, Multiply, and Divide Rational NumbersRational Number SystemIrrational Numbers and ApproximationsRatiosRatios and ProportionsProportional RelationshipsUnit RateAlgebraAlgebraic ExpressionsGenerate Equivalent ExpressionsQuantitative RelationshipsProportional Relationships and Linear EquationsEquations and InequalitiesEquation Solving and ReasoningLinear Equations and SystemsGraph Equations and InequalitiesSystems of EquationsReal-World Algebraic ProblemsQuantitative Reasoning with UnitsExpression StructureEquivalent Expression FormsRadicals and Integer ExponentsRational ExponentsRational and Irrational NumbersPolynomial OperationsPolynomial IdentitiesPolynomial Zeros and FactorsRational ExpressionsComplex Number OperationsComplex Numbers in PolynomialsComplex Numbers on PlaneStatistics & ProbabilityRepresent and Interpret DataData DistributionsStatistical VariabilityProbability ModelsCompound Event ProbabilitiesStatistical SamplingInterpret Categorical and Quantitative DataBivariate Data PatternsInterpret Linear ModelsComparing Two PopulationsRandom Processes in StatisticsIndependence and Conditional ProbabilityExpected ValuesProbability-Based Decision MakingStatistical Inference and ConclusionsFunctionsFunction Concepts and NotationDefine and Compare FunctionsInterpret Functions in ContextAnalyze Function RepresentationsModel Relationships with FunctionsIdentify Linear vs Exponential GrowthDistinguish Between Function TypesCompare Growth RatesInterpret Function ExpressionsBuild Functions from RelationshipsConstruct and Model FunctionsTransform and Combine FunctionsModel Comparison and SelectionSolve Exponential EquationsTrigonometryTrigonometric Ratios Involving Right TrianglesTrigonometric Functions and Unit CircleModel with Trigonometric FunctionsTrigonometric IdentitiesVectors & MatricesIntroduction to Vectors and MatricesVector QuantitiesVector OperationsMatrix OperationsCalculusLimits and ContinuityDerivative Concepts and NotationDerivative Rules and TechniquesApplications of DerivativesOptimization ProblemsRelated RatesCurve Sketching and AnalysisIntegration Concepts and NotationAntiderivatives and Indefinite IntegralsDefinite Integrals and AreaFundamental Theorem of CalculusIntegration TechniquesApplications of IntegrationDifferential EquationsSequences and SeriesParametric and Polar FunctionsVector-Valued Functions

Videos

Solving Right Triangles with the Pythagorean Theorem

Solving Right Triangles with the Pythagorean Theorem

This educational video provides a comprehensive review of the Pythagorean Theorem, a fundamental concept in geometry used to find missing side lengths in right triangles. The narrator, Justin, guides viewers through the definitions of key terms like "legs" and "hypotenuse," explains the core formula ($a^2 + b^2 = c^2$), and demonstrates how to correctly identify which sides correspond to which variables. The video is designed as a refresher for students who have seen the concept before but serves equally well as a first-time introduction. The content progresses from basic definitions to practical application, covering Pythagorean triples (like 3-4-5) and solving algebraic equations to find unknown lengths. It includes three distinct examples: checking a Pythagorean triple, finding a missing hypotenuse, and finding a missing leg. The final example introduces a higher-level skill: simplifying square roots (radicals) when the answer is not a perfect square, bridging geometry with algebraic skills. For educators, this video is an excellent tool for reinforcing geometric vocabulary and algebraic manipulation. It specifically addresses common student errors, such as misidentifying the hypotenuse, and provides clear, step-by-step visual modeling of the calculation process. It prepares students for more advanced topics like trigonometry by ensuring they grasp the relationship between the sides of a right triangle.

Miacademy & MiaPrep Learning ChannelMiacademy & MiaPrep Learning Channel

5mins 19s

Mastering the Rhombus: Properties, Area, and Angles

Mastering the Rhombus: Properties, Area, and Angles

This comprehensive math tutorial provides a deep dive into the geometric properties of a rhombus, guiding students from basic definitions to complex algebraic applications. The video begins by defining a rhombus as a special quadrilateral and parallelogram, explaining core features such as congruent sides, parallel opposite sides, and angle relationships. It visualizes how diagonals bisect angles, bisect each other, and intersect at perpendicular right angles, forming the foundation for area and perimeter calculations. The content progresses through a series of five increasing difficult example problems. These examples demonstrate how to calculate area using diagonals, determine perimeter using the Pythagorean theorem, and solve for missing angles using triangle sum properties. Later sections integrate algebra, challenging students to solve linear and quadratic equations to find side lengths and angle measures. The video concludes with a complex problem involving infinite solutions, encouraging critical thinking about mathematical identities. For educators, this video serves as an excellent resource for a Geometry or Algebra unit. It connects geometric concepts with algebraic solving skills, reinforcing the importance of the Pythagorean theorem and factoring quadratics in geometric contexts. The clear, step-by-step walkthroughs make it suitable for introducing new concepts, guided practice, or independent review for students struggling with the properties of quadrilaterals.

The Organic Chemistry TutorThe Organic Chemistry Tutor

22mins 30s

How to Classify Triangles by Angles and Sides

How to Classify Triangles by Angles and Sides

This educational video provides a comprehensive guide to classifying triangles based on two primary criteria: their angle measures and their side lengths. The narrator, Justin, walks viewers through the fundamental properties of triangles, starting with the Triangle Sum Theorem which states that interior angles always sum to 180 degrees. The video systematically breaks down classification categories including acute, right, obtuse, and equiangular for angles, as well as scalene, isosceles, and equilateral for sides. Key mathematical themes include geometric definitions, theorem application, and algebraic problem-solving within a geometric context. The video introduces and applies the Isosceles Triangle Theorem and its converse to show the relationship between opposite sides and angles. It also incorporates the Pythagorean Theorem to calculate missing side lengths in right triangles, bridging geometry with algebra and arithmetic involving square roots. For educators, this video serves as an excellent instructional tool for middle and high school geometry units. It includes built-in pause points for students to calculate missing values, making it highly interactive. The content moves beyond simple identification by requiring students to solve for variables (x) and use deductive reasoning to determine classifications, making it suitable for introducing new concepts or reviewing for assessments.

Miacademy & MiaPrep Learning ChannelMiacademy & MiaPrep Learning Channel

10mins 34s

Finding Missing Sides of Right Triangles Using the Pythagorean Theorem

Finding Missing Sides of Right Triangles Using the Pythagorean Theorem

This instructional video provides a comprehensive review of the Pythagorean Theorem, a fundamental concept in geometry used to find the missing side of a right triangle. Narrated by Justin, the lesson begins by defining the specific parts of a right triangle—identifying the legs and the hypotenuse—and explaining the importance of correctly labeling them before applying the formula $a^2 + b^2 = c^2$. The video walks viewers through two distinct examples to demonstrate the theorem's application in different scenarios. The first example solves for an unknown hypotenuse using a standard 5-12-13 triangle. The second example presents a more complex problem where the hypotenuse is known, requiring students to solve for a missing leg; this example also demonstrates how to simplify radicals (square roots) for an exact answer rather than using decimal approximations. Designed for middle and high school math students, this video serves as an excellent resource for introducing the concept or reviewing it before moving on to the Distance Formula. It effectively models mathematical thinking, algebraic manipulation, and the procedure for simplifying square roots, making it a versatile tool for classroom instruction, homework support, or test preparation.

Miacademy & MiaPrep Learning ChannelMiacademy & MiaPrep Learning Channel

6mins 23s

ACT Math Practice Test: Review of Algebra, Geometry, and Trig Concepts

ACT Math Practice Test: Review of Algebra, Geometry, and Trig Concepts

This comprehensive video tutorial serves as an intensive review for the ACT Math section, covering a wide array of topics crucial for high school students preparing for college entrance exams. The content is structured as a series of 31 practice problems that mimic the style and difficulty of actual ACT questions. It progresses through various mathematical domains including pre-algebra, elementary algebra, intermediate algebra, coordinate geometry, plane geometry, and trigonometry. The video adopts a pause-and-practice format, encouraging active participation where viewers attempt each problem before watching the detailed step-by-step solution. Key themes explored in this review include solving linear and quadratic equations, working with functions, understanding geometric properties of polygons and circles, applying trigonometric ratios (SOH CAH TOA) and identities, and analyzing statistical data. The video also places a strong emphasis on real-world application problems involving percentages, sales tax, discounts, and unit conversions. Particular attention is given to algebraic manipulation strategies, such as solving systems of equations and simplifying complex expressions, as well as test-taking tactics like identifying key information in word problems. For educators and students, this video is a valuable resource for standardized test preparation. It allows teachers to identify specific areas of weakness in student understanding by isolating problem types (e.g., if a student struggles with problem 10, they need more support with circle geometry). The step-by-step explanations model clear mathematical reasoning, demonstrating not just *how* to get the right answer, but *why* specific methods work. This makes it an excellent tool for flipped classrooms, homework support, or intensive boot-camp style review sessions prior to test dates.

The Organic Chemistry TutorThe Organic Chemistry Tutor

20mins 33s

Mastering Trigonometric Ratios and SOH CAH TOA

Mastering Trigonometric Ratios and SOH CAH TOA

This comprehensive mathematics tutorial introduces the fundamental concepts of trigonometric ratios within right-angled triangles. The video systematically explains the definitions of sine, cosine, and tangent using the mnemonic device SOH CAH TOA, demonstrating how to identify the opposite, adjacent, and hypotenuse sides relative to a specific angle. Through clear, hand-drawn examples on a blackboard style interface, the narrator guides viewers from basic ratio identification to more complex applications involving special right triangles and inverse functions. The content covers several key topics including calculating ratios for standard triangles (like 8-15-17 and 3-4-5), determining exact trigonometric values for special angles (30, 45, and 60 degrees), and summarizing these values in a reference table. The video progresses to practical problem-solving techniques, showing students how to use algebra to find missing side lengths when given an angle and one side, as well as how to use inverse trigonometric functions (specifically arctan) to calculate missing angles when given two sides. Ideally suited for high school geometry and trigonometry classes, this video serves as both an introduction and a practice resource. The narrator frequently encourages active learning by prompting viewers to pause the video and attempt problems before seeing the solution. This format allows teachers to use the video as an interactive classroom tool for direct instruction, guided practice, or independent review, effectively addressing common student difficulties in setting up and solving trigonometric equations.

The Organic Chemistry TutorThe Organic Chemistry Tutor

17mins 52s

Materials

Geometry Blueprint Reference

Geometry Blueprint Reference

A comprehensive two-page printable geometry anchor chart for grades 3-8, themed as a technical blueprint. Features grade-banded formulas for perimeter, area, volume, surface area, and circles, including the Pythagorean theorem and common measurement conversions. Organized with MathJax for professional notation.

KB

Karen Brown

Right Triangle Blueprint Reading Handout

Right Triangle Blueprint Reading Handout

A high school geometry reading assignment and reflection guide covering the Pythagorean theorem, geometric proofs, triangle classification using the converse, and coordinate distance applications, followed by eight analytical reflection questions.

AR

Angie Rice

Geometry Essentials Reference Guide

Geometry Essentials Reference Guide

A comprehensive two-page reference guide deconstructing the most essential high school geometry standard: Right Triangle Trigonometry (HSG-SRT.C.8 and State Equivalents). Features conceptual definitions, SOH CAH TOA ratio models, special right triangles, real-world elevation and depression modeling, and step-by-step exemplar problem solutions.

Sequences

Equation Balancing Student Packet

Distance Detectives

A highly visual geometry unit focused on applying algebraic formulas to coordinate planes. Students use coordinate grids, step-by-step graphic organizers, and tactile representations to solve real-world distance and segment length problems.

D

deeohnny.jackson

64
Regents Mastery Blueprint Study Guide

Regents Mastery Suite

A comprehensive review suite for the New York State Mathematics Regents exams, including Algebra 1, Geometry, and Algebra 2, featuring mastery blueprints, calculator strategies, and exam-taking tips.

KB

Kayla Borozny

15
Maths 3eme Carte Mentale Document

Feuilles de Route Maths

Un ensemble de cartes mentales et d'infographies pédagogiques pour guider les élèves de collège (4ème, 3ème) dès la rentrée.

E

Enseignante

4
Week One Marathon Log

Math Marathon TSIA2 Prep

A comprehensive 15-day TSIA2 math review sequence featuring daily warm-up questions and weekly progress logs for students. The program covers all four TSIA2 domains through a "Math Marathon" theme.

PR

Penne Reed

4
Strategy Blueprint Slides

ACT Math Mastery

A comprehensive ACT Math preparation program focusing on essential strategies, high-yield Algebra and Geometry concepts, and realistic practice to boost scores.

AL

ava larumbe

26
Correction Decryptee Brevet 2026

Objectif Brevet 2026

Sujet de mathématiques corrigé et décrypté pas à pas pour les élèves de 3ème. Inclut des rappels de cours méthodologiques, des astuces de calcul et des alertes sur les pièges classiques.

MW

Myriam Wb

1

Lessons

DNB Chrono Livret de Révision

Brevet Express

Un kit complet de révision de dernière minute pour le DNB de Mathématiques, comprenant un sujet blanc guidé pas-à-pas pour les élèves et un corrigé détaillé avec barème pour l'enseignant.

E

Enseignante

4
Math Screener Student Booklet

8th Grade Math Diagnostic Screener

A comprehensive 8th-grade math screener diagnostic tool designed to identify students for Tier 2 and Tier 3 interventions. Includes a 4-page student booklet, a matching step-by-step answer key, and an instructional rubric, placement guide, and class data tracker spanning 6th, 7th, and 8th-grade standards.

B

Bennington

3
Circle Secrets Slides

Circle Secrets

A comprehensive 60-minute exploration of circle anatomy, focusing on identifying all parts of a circle and applying theorems related to tangent lines. Students will engage with visual slides, a vocabulary matching activity, and a rigorous practice set.

EO

Edobor Omosigho

5
Right Triangle Mastery Slides

Right Triangle Mastery

A foundational geometry lesson on the Pythagorean Theorem, guiding students from right triangle anatomy and conceptual proofs to computational fluency and real-world problem solving.

MA

Mary Ann Valiente

3
Consecutive Quadratics Practice Guide

Consecutive Integer Quadratics

A focused 10th-grade algebra lesson on modeling real-world and algebraic relationships using quadratic equations with consecutive odd and even integers. Features structured reference materials and an in-depth teacher solutions key.

AR

Angie Rice

4
TSIA2 Math Formula Reference Sheet

TSIA2 Math Mastery

A comprehensive practice suite designed to prepare students for the TSIA2 Mathematics placement test. Includes a realistic 20-question practice exam, a detailed step-by-step solutions guide, and a targeted formula reference sheet.

P

psreed75

3