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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

Expression Mastery

A comprehensive pre-algebra sequence covering algebraic expressions, grouping rules, order of operations with exponents, and the distributive property with like terms.

Kkandrews
Order Ops Challenge

A structured, scaffolded practice lesson on the order of operations featuring exponents, grouping symbols, and multi-step evaluation. Students advance across three tiers of complexity alongside error analysis and equation-building challenges.

Distributive Power

A targeted practice lesson on expanding algebraic expressions using the distributive property, multiplying negative terms, and combining like terms. Features visual area models, scaffolded tiers, and misconception analysis.

Expression Mastery

A comprehensive pre-algebra sequence covering algebraic expressions, grouping rules, order of operations with exponents, and the distributive property with like terms.

Kkandrews

Full credit requires showing brackets resolution

#9 \(3 \cdot [4^2 - (5 + 2 \cdot 3)]\)

Inner ( ): \(5 + 6 = 11\)

Brackets [ ]: \(4^2 - 11 = 16 - 11 = 5\)

Outer: \(3 \cdot 5 = 15\)

Answer: 15

#10 \(\dfrac{5^2 - 3^2}{2^3 - 4}\)

Numerator: \(25 - 9 = 16\)

Denominator: \(8 - 4 = 4\)

Division: \(\frac{16}{4} = 4\)

Answer: 4

#11 \(2 \cdot (3 + 1)^2 - [18 \div (2 \cdot 3)]\)

Term 1: \(2 \cdot (4)^2 = 2 \cdot 16 = 32\)

Term 2: \([18 \div 6] = 3\)

Subtract: \(32 - 3 = 29\)

Answer: 29

#12 \(\dfrac{4 \cdot (7 - 2) + 2^3}{14 - 2 \cdot 3}\)

Numerator: \(4 \cdot 5 + 8 = 20 + 8 = 28\)

Denominator: \(14 - 6 = 8\)

Divide / Reduce: \(\frac{28}{8} = \frac{7}{2} = 3.5\)

Answer: 3.5 (or 7/2)

Analysis Key

Error Detective: Explanations & Corrections

#13 Case A Key \(24 - 4 \cdot 2^2 + 5\)

Error Identified: Subtracted \(24 - 4\) before evaluating the exponent \(2^2\) and multiplying by 4.

\(= 24 - 4 \cdot 4 + 5 = 24 - 16 + 5 = 8 + 5 = 13\)

Correct Answer: 13

#14 Case B Key \(18 \div 3 \cdot 2 + 4^2\)

Error Identified: Multiplied \(3 \cdot 2 = 6\) before dividing. Division and multiplication must proceed Left → Right.

\(= 6 \cdot 2 + 16 = 12 + 16 = 28\)

Correct Answer: 28

Puzzle Key

Equation Architect: Parentheses Placements

#15 Solution Target: 32

(8 + 4 × 3) - 2² = (8 + 12) - 4 = 16 ≠ 32 → Try: (8 + 4) × 3 - 2² = 12 × 3 - 4 = 36 - 4 = 32 ✓

Placement: (8 + 4) × 3 - 2² = 32

#16 Solution Target: 24

30 ÷ (2 + 3) × 4 = 30 ÷ 5 × 4 = 6 × 4 = 24 ✓

Placement: 30 ÷ (2 + 3) × 4 = 24

PEMDAS & Exponents • Teacher Answer Key Page 2 of 2

#16 Triangle Perimeter Geometry

A triangle has three side lengths: \(a = 2(x + 3)\), \(b = 4x - 1\), and \(c = 3(2x - 4)\). Write a fully simplified expression for its perimeter \(P = a + b + c\).

Simplified Perimeter \(P\):

The Distributive Property • Lesson Practice Page 2 of 2

#12 \(-3(2m - 1) + 4(3m + 5)\)

Distribute: \(-6m + 3 + 12m + 20\)

Combine: \((-6m + 12m) + (3 + 20) = 6m + 23\)

Simplified: \(6m + 23\)

Analysis Key

Error Detective: Explanations & Corrections

#13 Case A Key \(-5(2x - 4)\)

Error Identified: Sign error on the second term: \(-5 \cdot (-4) = +20\), not \(-20\).

\(= -5(2x) - 5(-4) = -10x + 20\)

Correct Answer: \(-10x + 20\)

#14 Case B Key \(3 + 2(x + 4)\)

Error Identified: Violated PEMDAS: added \(3 + 2 = 5\) before multiplying/distributing the 2 into the parentheses.

\(= 3 + 2x + 8 = 2x + 11\)

Correct Answer: \(2x + 11\)

Application Key

Geometric Application: Full Solutions

#15 Rectangle Key \(w = 4, l = 3x + 5\)

Area: \(4(3x + 5) = 12x + 20\)

Perimeter: \(2(3x + 5) + 2(4) = 6x + 10 + 8 = 6x + 18\)

Area: \(12x + 20\)

Perimeter: \(6x + 18\)

#16 Triangle Perimeter Key Sides: \(2(x + 3), 4x - 1, 3(2x - 4)\)

Expand: \(2x + 6 + 4x - 1 + 6x - 12\)

Group: \((2x + 4x + 6x) + (6 - 1 - 12)\)

Simplify: \(12x - 7\)

Perimeter \(P\): \(12x - 7\)

The Distributive Property • Teacher Answer Key Page 2 of 2

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