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Algebra I

Level up your algebra skills, learn about functions and graphing, and dive deep into quadratics.



Linear Equations

Nonlinear Equations




Equations & Inequalities
24 topics
1.1. Linear Equations
1.1.1. Solving Linear Equations With Unknown Coefficients
1.1.2. Solving Linear Equations With Unknown Coefficients by Factoring
1.1.3. Solving Linear Inequalities With Unknown Parameters
1.1.4. Solving Many-Variable Equations
1.2. Modeling With Linear Equations
1.2.1. Interpreting Linear Expressions
1.2.2. Modeling With Linear Equations
1.2.3. Consecutive Integer Problems
1.2.4. Speed, Distance, Time Problems
1.2.5. Further Speed, Distance, Time Problems
1.2.6. Modeling Work Problems
1.2.7. Modeling Mixture Problems
1.3. Linear Inequalities
1.3.1. Solving Compound Inequalities
1.3.2. Interval Notation
1.3.3. Unbounded Intervals
1.3.4. Unions of Intervals
1.3.5. Intersections of Intervals
1.3.6. Compound OR Inequalities
1.3.7. Compound AND Inequalities
1.3.8. Introduction to Modeling With Inequalities
1.3.9. Modeling With One-Step Inequalities
1.3.10. Modeling With Two-Step Inequalities
1.4. Nonlinear Equations
1.4.1. Solving Equations Using the Square Root Method
1.4.2. Solving Equations With Odd Exponents Using the Nth Root Method
1.4.3. Solving Equations With Even Exponents Using the Nth Root Method
Two-Variable Equations & Inequalities
28 topics
2.5. Graphs of Linear Equations
2.5.1. Equations of Lines in Slope-Intercept Form
2.5.2. Finding Properties of Lines Given in Slope-Intercept Form
2.5.3. Equations of Lines in Point-Slope Form
2.5.4. Equations of Lines in Standard Form
2.5.5. Determining Properties of Lines Given in Standard Form
2.6. Modeling With Two-Variable Linear Equations
2.6.1. Modeling With Linear Equations in Two Variables
2.6.2. Further Modeling With Linear Equations in Two Variables
2.6.3. Analyzing and Interpreting Graphs of Linear Equations
2.6.4. Distance-Time Graphs
2.6.5. Calculating Acceleration From a Speed-Time Graph
2.6.6. Calculating Distance From a Speed-Time Graph
2.7. Systems of Equations
2.7.1. Introduction to the Elimination Method
2.7.2. Solving Systems of Linear Equations Using Elimination: One Transformation
2.7.3. Solving Systems of Linear Equations Using Elimination: Two Transformations
2.7.4. Systems of Linear Equations With Fractional Coefficients
2.7.5. Systems of Linear Equations With Decimal Coefficients
2.7.6. Systems of Equations With No Solutions and Infinitely Many Solutions
2.7.7. Calculating the Intersection of Two Lines
2.7.8. Modeling Number Problems Using Systems of Linear Equations
2.7.9. Modeling Coin Problems Using Systems of Linear Equations
2.7.10. Solving Systems of Nonlinear Equations Using Graphs
2.7.11. Approximating Solutions to Systems of Linear Equations
2.7.12. Approximating Solutions to Systems of Nonlinear Equations
2.8. Two-Variable Linear Inequalities
2.8.1. Graphing Strict Two-Variable Linear Inequalities
2.8.2. Graphing Non-Strict Two-Variable Linear Inequalities
2.8.3. Further Graphing of Two-Variable Linear Inequalities
2.8.4. Solving Systems of Linear Inequalities
2.8.5. Modeling With Two-Variable Linear Inequalities
13 topics
3.9. Working With Units
3.9.1. Unit Conversions Using Base Units of Mass
3.9.2. Two-Step Unit Conversions
3.9.3. Unit Conversions Using Base Units of Length
3.9.4. Unit Conversions Using Units of Time
3.9.5. Converting Units of Area to Smaller Units
3.9.6. Converting Units of Area to Larger Units
3.9.7. Determining Units in Formulas
3.9.8. Selecting Units for Rates of Change
3.9.9. Converting Between Mixed Units
3.9.10. Degrees of Accuracy
3.10. Direct and Inverse Variation
3.10.1. Inverse Variation
3.10.2. Modeling with Direct Variation
3.10.3. Modeling With Inverse Variation
Radical Expressions
11 topics
4.11. Radical Expressions
4.11.1. The Square Root of a Perfect Square With Algebraic Expressions
4.11.2. The Square Root of a Perfect Square With Domain Restrictions
4.11.3. The Cube Root of a Perfect Cube With Algebraic Expressions
4.11.4. Simplifying Square Root Expressions Using the Product Rule
4.11.5. Combining Radical Expressions Using the Product Rule
4.11.6. Simplifying Square Root Expressions Using the Quotient Rule
4.11.7. Evaluating Algebraic Radical Expressions
4.11.8. Adding and Subtracting Radical Expressions
4.11.9. Rationalizing Denominators of Algebraic Expressions
4.11.10. Rationalizing Denominators With Two Terms
4.11.11. Solving Radical Equations
Rational Expressions & Equations
7 topics
5.12. Rational Expressions
5.12.1. Equivalent Expressions With Fractions
5.12.2. Simplifying Rational Expressions
5.12.3. Simplifying Rational Expressions by Factoring
5.13. Rational Equations
5.13.1. Solving Rational Equations Containing One Fractional Term
5.13.2. Solving Rational Equations Using Cross-Multiplication
5.13.3. Solving Rational Equations Containing Binomials Using Cross-Multiplication
5.13.4. Solving Rational Equations Using the Flip Method
17 topics
6.14. Functions
6.14.1. Introduction to Functions
6.14.2. Visual Representations of Functions
6.14.3. Graphs of Functions
6.14.4. The Domain of a Function
6.14.5. The Vertical Line Test
6.14.6. Global Extrema of Functions
6.14.7. End Behavior of Functions
6.14.8. The Range of a Function
6.14.9. The Range of a Function: Advanced Cases
6.14.10. The Roots of a Function
6.14.11. Increasing and Decreasing Functions
6.14.12. Piecewise Functions
6.14.13. Modeling With Linear Functions
6.14.14. The Arithmetic of Functions
6.14.15. Composition of Functions
6.14.16. Finding Algebraic Expressions of Composite Functions
6.14.17. Introduction to Inverse Functions
Absolute Value
14 topics
7.15. Absolute Value Expressions, Equations & Inequalities
7.15.1. Absolute Value Expressions
7.15.2. Rules of Absolute Value
7.15.3. Further Rules of Absolute Value
7.15.4. Absolute Value Equations
7.15.5. Further Absolute Value Equations
7.15.6. Equations Connecting Absolute Value and Linear Functions
7.15.7. Absolute Value Equations With Extraneous Solutions
7.15.8. Absolute Value Inequalities
7.16. Absolute Value Functions
7.16.1. Absolute Value Graphs
7.16.2. Vertical Reflections of Absolute Value Graphs
7.16.3. Stretches of Absolute Value Graphs
7.16.4. Combining Transformations of Absolute Value Graphs
7.16.5. Domain and Range of Absolute Value Functions
7.16.6. Roots of Absolute Value Functions
Exponential Functions
22 topics
8.17. Rules of Exponents
8.17.1. Writing Radical Expressions Using Fractional Exponents
8.17.2. The Product Rule for Exponents With Algebraic Expressions
8.17.3. The Quotient Rule for Exponents With Algebraic Expressions
8.17.4. The Power Rule for Exponents With Algebraic Expressions
8.17.5. The Power of Product Rule With Algebraic Expressions
8.17.6. The Power of Quotient Rule With Algebraic Expressions
8.17.7. Combining the Rules of Exponents With Algebraic Expressions
8.18. Exponential Expressions & Equations
8.18.1. Solving Exponential Equations with Integer Solutions
8.18.2. Solving Exponential Equations with Fractional Solutions
8.18.3. Creating Exponential Growth Expressions
8.18.4. Creating Exponential Decay Expressions
8.19. Exponential Functions
8.19.1. Exponential Functions
8.19.2. Modeling Exponential Growth With Functions
8.19.3. Interpreting Exponential Growth
8.19.4. Solving Exponential Growth Problems
8.19.5. Modeling Exponential Decay With Functions
8.19.6. Interpreting Exponential Decay
8.19.7. Solving Exponential Decay Problems
8.19.8. Linear vs. Exponential Growth and Decay
8.19.9. Linear vs. Exponential Growth and Decay Models
8.19.10. Graphing Exponential Growth Functions
8.19.11. Graphing Exponential Decay Functions
19 topics
9.20. Polynomials
9.20.1. Introduction to Polynomials
9.20.2. The Degree of a Polynomial
9.20.3. Simplifying Polynomials
9.20.4. The Distributive Law for Polynomials
9.20.5. Adding and Subtracting Polynomials
9.20.6. Monomials, Binomials and Trinomials
9.20.7. Multiplying Binomials
9.20.8. Multiplying Polynomials
9.20.9. Squaring Binomials
9.20.10. Expanding Binomials Using Pascal's Triangle
9.20.11. The Difference of Squares Formula
9.21. Factoring Polynomials
9.21.1. The Greatest Common Factor of Two Monomials
9.21.2. Factoring Simple Polynomials Using Greatest Common Factors
9.21.3. Factoring Perfect Square Trinomials
9.21.4. Factoring Perfect Square Trinomials With Leading Coefficients
9.21.5. Factoring Differences of Squares
9.21.6. Factoring Trinomials
9.21.7. Factoring Trinomials Using Common Factors
9.21.8. Factoring Trinomials With Leading Coefficients
Quadratic Equations & Functions
33 topics
10.22. Quadratic Equations
10.22.1. Introduction to Quadratic Equations
10.22.2. Solving Perfect Square Quadratic Equations
10.22.3. Perfect Square Quadratic Equations with One or No Solutions
10.22.4. The Zero Product Rule for Solving Quadratic Equations
10.22.5. Solving Quadratic Equations Using a Difference of Squares
10.22.6. Solving Quadratic Equations with No Constant Term
10.22.7. Solving Quadratic Equations by Factoring
10.22.8. Solving Quadratic Equations with Leading Coefficients by Factoring
10.22.9. Completing the Square
10.22.10. Completing the Square With Odd Linear Terms
10.22.11. Completing the Square With Leading Coefficients
10.22.12. Solving Quadratic Equations by Completing the Square
10.22.13. Solving Quadratic Equations With Leading Coefficients by Completing the Square
10.22.14. The Quadratic Formula
10.22.15. The Discriminant of a Quadratic Equation
10.22.16. Modeling With Quadratic Equations
10.23. Quadratic Functions
10.23.1. Graphing Elementary Quadratic Functions
10.23.2. Vertical Reflections of Quadratic Functions
10.23.3. Graphs of General Quadratic Functions
10.23.4. Roots of Quadratic Functions
10.23.5. The Discriminant of a Quadratic Function
10.23.6. Calculating the Axis of Symmetry of a Parabola
10.23.7. The Average of the Roots Formula
10.23.8. The Vertex Form of a Parabola
10.23.9. Writing the Equation of a Parabola in Vertex Form
10.23.10. Domain and Range of Quadratic Functions
10.23.11. Finding Intersections of Lines and Quadratic Functions
10.24. Modeling With Quadratic Functions
10.24.1. Modeling Downwards Vertical Motion
10.24.2. Modeling Upwards Vertical Motion
10.24.3. Vertical Motion
10.24.4. Revenue, Cost, and Profit Functions
10.24.5. Constructing Revenue, Cost, and Profit Functions
10.24.6. Maximizing Profit and Break-Even Points
18 topics
11.25. Introduction to Sequences
11.25.1. Introduction to Sequences
11.25.2. Recursive Sequences
11.25.3. Fibonacci Sequences
11.26. Arithmetic Sequences
11.26.1. Arithmetic Sequences
11.26.2. Recursive Formulas for Arithmetic Sequences
11.26.3. The Nth Term of an Arithmetic Sequence
11.26.4. Translating Between Explicit and Recursive Formulas for Arithmetic Sequences
11.26.5. Finding the Common Difference of an Arithmetic Sequence Given Two Terms
11.26.6. Finding the Nth Term of an Arithmetic Sequence Given Two Terms
11.26.7. Determining Indexes of Terms in Arithmetic Sequences
11.26.8. Solving for Variables in Arithmetic Sequences
11.26.9. Modeling With Arithmetic Sequences
11.27. Geometric Sequences
11.27.1. Introduction to Geometric Sequences
11.27.2. The Recursive Formula for a Geometric Sequence
11.27.3. Finding the Nth Term of a Geometric Sequence
11.27.4. Translating Between Explicit and Recursive Formulas for Geometric Sequences
11.27.5. Finding the Common Ratio of a Geometric Sequence Given Two Terms
11.27.6. Finding the Index of a Term in a Geometric Sequence