# Algebra

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Algebra is the method for solving equations and expressing formulas. Created by Khan Academy.

Recommended that you have a good foundation in Pre-algebra before taking this course.

###### Average Course Length

20 hours

###### Skill Level

Intermediate

##### Pick a lesson

1: The Beauty of Algebra

2: Origins of Algebra

3: Abstract-ness

4: Descartes and Cartesian Coordinates

5: Variables Expressions and Equations

6: Simple Equations

7: Equations 2

8: Equations 3

9: Algebra: Linear Equations 4

10: Algebra: Solving Inequalities

11: Algebra: graphing lines 1

12: Algebra: Slope and Y-intercept intuition

13: Algebra: Slope

14: Algebra: Slope 2

15: Algebra: Slope 3

16: Algebra: Equation of a line

17: Slope and Y-intercept Intuition

18: Averages

19: Integer sums

20: Taking percentages

21: Growing by a percentage

22: Another Percent Word Problem

23: More percent problems

24: systems of equations

25: Introduction to Ratios

26: Ratio problem with basic algebra

27: More advanced ratio problem--with Algebra

28: Alternate Solution to Ratio Problem

29: Introduction to Ratios

30: Advanced ratio problems

31: Age word problems 1

32: Age word problems 2

33: Age word problems 3

34: Level 1 multiplying expressions

35: Solving a quadratic by factoring

36: Introduction to i and Imaginary Numbers

37: Calculating i Raised to Arbitrary Exponents

38: i as the Principal Root of -1 (a little technical)

39: Complex Numbers (part 1)

40: Complex Numbers (part 2)

41: Introduction to the quadratic equation

42: Quadratic Equation part 2

43: Completing the square

44: Quadratic Formula (proof)

45: Quadratic Inequalities

46: Quadratic Inequalities (Visual Explanation)

47: Introduction to functions

48: Functions Part 2

49: Functions (Part III)

50: Functions (part 4)

51: Domain of a function

52: Proof: log a + log b = log ab

53: Proof: A(log B) = log (B^A), log A - log B = log (A/B)

54: Proof: log_a (B) = (log_x (B))/(log_x (A))

55: Algebraic Long Division

56: Introduction to Conic Sections

57: Conic Sections: Intro to Circles

58: Conic Sections: Intro to Ellipses

59: Conic Sections: Intro to Hyperbolas

60: Conic Sections: Hyperbolas 2

61: Conic Sections: Hyperbolas 3

62: Identifying Conics 1

63: Identifying Conics 2

64: Conic Identification 3

65: Foci of an Ellipse

66: Foci of a Hyperbola

67: Proof: Hyperbola Foci

68: Partial Fraction Expansion 1

69: Partial Fraction Expansion 2

70: Partial Fraction Expansion 3

71: Parabola Focus and Directrix 1

72: Focus and Directrix of a Parabola 2

73: Two Passing Bicycles Word Problem

74: Passed Bike Word Problem

75: Passing Trains

76: Overtaking Word Problem

77: Early Train Word Problem

78: Officer on Horseback

79: Rational Inequalities

80: Rational Inequalities 2

81: Interesting Polynomial Coefficient Problem

82: Geometric series sum to figure out mortgage payments

83: Introduction to Function Inverses

84: Function Inverse Example 1

85: Function Inverses Example 2

86: Function Inverses Example 3

87: Direct and Inverse Variation

88: Recognizing Direct and Inverse Variation

89: Recognizing Odd and Even Functions

90: Connection between even and odd numbers and functions

91: New Operator Definitions

92: Proof by Induction

93: Alternate Proof to Induction for Integer Sum

94: Writing Proportions

95: Coverting Repeating Decimals to Fractions 1

96: Coverting Repeating Decimals to Fractions 2