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ACT
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Concepts
ACT English
Correcting Grammatical Errors
Phrase, Clause, and Sentence Errors
Appositive and Interrupting Phrase Errors
+2 topics
Appositive Errors
Interrupting Phrase Errors
Conjunction Errors
+3 topics
Correlative Conjunction Errors
Other Conjunction Errors
Subordinating Conjunction Errors
Modifier Placement Errors
+3 topics
Ambiguous Modifier Errors
Dangling Modifier Errors
Misplaced or Interrupting Modifier Errors
Other Phrase, Clause, and Sentence Errors
+2 topics
Parallel Structure Errors
Sentence Fragment and Sentence Combination Errors
Punctuation Errors
Apostrophe Errors
Colon Errors
Comma Errors
Errors Involving Hyphens, Dashes, and Parentheses
Period, Exclamation Point, and Question Mark Errors
Quotation Mark Errors
Semicolon Errors
Word Usage Errors
Agreement Errors
+11 topics
Modifier-Word Modified Agreement Errors
+3 topics
Modifier-Word Modified Countability Errors
Modifier-Word Modified Number Errors
Other Modifier-Word Modified Agreement Errors
Pronoun-Antecedent Agreement Errors
+3 topics
Other Pronoun-Antecedent Errors
Pronoun-Antecedent Gender Errors
Pronoun-Antecedent Number Errors
Subject-Verb Agreement Errors
+2 topics
Compound Subject Errors
Simple Subject Errors
Usage Errors
+17 topics
Other Usage Errors
+4 topics
Comparative and Superlative Adjective and Adverb Errors
Conventional and Idiomatic Usage Errors
Other Adjective and Adverb Errors
Preposition Errors
Pronoun Usage Errors
+6 topics
Other Pronoun Errors
+2 topics
Other Pronoun Usage Errors
Relative Pronoun Usage Errors
Pronoun Case Errors
+2 topics
Possessive Pronoun Errors
Subjective and Objective Pronoun Errors
Verb Formation Errors
+4 topics
Other Verb Usage Errors
Verb Mood Errors
Verb Tense Errors
Verb Voice Errors
Writing and Revising Effectively
Inserting and Removing Content
Inserting Content
Removing Content
Reorganizing Content
Separating, Combining, or Reordering Paragraphs
Separating, Combining, or Reordering Sentences
Revising Content
Analyzing Contextual Relevance
Analyzing Effectiveness
Avoiding Ambiguity and Redundancy
Introductions, Transitions, and Conclusions
Understanding Referents
Word Choice, Style, and Tone
ACT Math
Algebra
Algebraic Fractions
How to evaluate a fraction
How to find excluded values
How to find inverse variation
How to simplify a fraction
How to solve for a variable as part of a fraction
Algebraic Functions
How to find domain and range of the inverse of a relation
How to find f(x)
How to find the domain of a function
How to use the quadratic function
Coordinate Plane
Circles
+1 topic
How to find the equation of a circle
Graphing
+9 topics
How to graph a function
How to graph a line
How to graph a point
How to graph a quadratic function
How to graph a two-step inequality
How to graph an exponential function
How to graph an ordered pair
How to graph complex numbers
How to graph inverse variation
Lines
+20 topics
Distance Formula
+1 topic
How to find the length of a line with distance formula
Midpoint Formula
+2 topics
How to find the endpoints of a line segment
How to find the midpoint of a line segment
Other Lines
+3 topics
How to find out if a point is on a line with an equation
How to find the equation of a line
How to find the slope of a line
Parallel Lines
+3 topics
How to find out if lines are parallel
How to find the equation of a parallel line
How to find the slope of parallel lines
Perpendicular Lines
+3 topics
How to find out if lines are perpendicular
How to find the equation of a perpendicular line
How to find the slope of a perpendicular line
Tangent Lines
+2 topics
How to find the equation of a tangent line
How to find the slope of a tangent line
Transformation
+1 topic
How to find transformation for an analytic geometry equation
x and y Intercept
+2 topics
How to find the equation of a curve
How to find x or y intercept
Distributive Property
FOIL
+2 topics
How to use FOIL with the distributive property
How to use the grid method for FOIL
Equations / Inequalities
Factoring Equations
+1 topic
How to factor an equation
Inequalities
+4 topics
How to find the solution to an inequality with addition
How to find the solution to an inequality with division
How to find the solution to an inequality with multiplication
How to find the solution to an inequality with subtraction
Linear / Rational / Variable Equations
+3 topics
How to find out when an equation has no solution
How to find the solution to a rational equation with LCD
How to find the solution to an equation
Quadratic Equations
+2 topics
How to factor the quadratic equation
How to find the solution to a quadratic equation a1
Solution Sets
+1 topic
How to find a solution set
Systems of Equations
+1 topic
How to find the solution for a system of equations
Exponents
Exponential Operations
+4 topics
How to add exponents
How to divide exponents
How to multiply exponents
How to subtract exponents
Exponential Ratios
+1 topic
How to find a ratio of exponents
Exponents and Rational Numbers
+2 topics
How to find a rational number from an exponent
How to find an exponent from a rational number
Exponents and the Distributive Property
+1 topic
How to use FOIL with exponents
Logarithms
+1 topic
How to find a logarithm
Other Exponents
+1 topic
How to use scientific notation
Pattern Behaviors in Exponents
+2 topics
How to find compound interest
How to find patterns in exponents
Squaring / Square Roots / Radicals
+11 topics
Complex Numbers
+4 topics
How to add complex numbers
How to divide complex numbers
How to multiply complex numbers
How to subtract complex numbers
Factoring Squares
+1 topic
How to factor a common factor out of squares
Square of Difference
+1 topic
How to find the square of difference
Square of Sum
+1 topic
How to find the square of a sum
Expressions
Evaluating Expressions
+1 topic
How to evaluate algebraic expressions
Rational Expressions
+6 topics
How to add rational expressions with a common denominator
How to add rational expressions with different denominators
How to divide rational expressions
How to evaluate rational expressions
How to multiply rational expressions
How to subtract rational expressions with different denominators
Simplifying Expressions
+1 topic
How to simplify an expression
Matrices
Matrix Combinations
+1 topic
How to find combinations with a matrix
Other Matrices
+3 topics
How to add matrices
How to find an answer with a matrix
How to subtract matrices
Scalar interactions with Matrices
+2 topics
How to find scalar interactions with a matrix
How to multiply a matrix by a scalar
Variables
Direct and Inverse Variation
+2 topics
How to use the direct variation formula
How to use the inverse variation formula
Factoring
+1 topic
How to factor a variable
Monomials
+3 topics
How to divide monomial quotients
How to multiply a monomial by a polynomial
How to multiply monomial quotients
Polynomials
+25 topics
Binomials
+10 topics
Binomial Denominators
+1 topic
How to find the solution of a rational equation with a binomial denominator
Binomials and FOIL
+1 topic
How to multiply binomials with the distributive property
Coefficients
+1 topic
How to find the value of the coefficient
Other Binomials
+1 topic
How to find the solution to a binomial problem
Simplifying
+1 topic
How to simplify binomials
Factoring Polynomials
+1 topic
How to factor a polynomial
Polynomial Operations
+5 topics
How to add polynomials
How to divide polynomials
How to find the degree of a polynomial
How to multiply polynomials
How to subtract polynomials
Trinomials
+5 topics
How to add trinomials
How to divide trinomials
How to factor a trinomial
How to multiply trinomials
How to subtract trinomials
Arithmetic
Basic Squaring / Square Roots
Factoring Common Factors of Squares and Square Roots
+1 topic
How to find the common factor of square roots
Other Squaring / Square Roots
+1 topic
How to find the square of an integer
Simplifying Square Roots
+2 topics
How to find the common factors of squares
How to simplify square roots
Square Roots and Operations
+5 topics
How to add square roots
How to divide square roots
How to find a ratio of square roots
How to multiply square roots
How to subtract square roots
Decimals
Basic Squaring / Square Roots
+2 topics
How to find the square root of a decimal
How to square a decimal
Decimals with Fractions
+3 topics
How to find decimal fractions
How to find the decimal equivalent of a fraction
How to find the fractional equivalent of a decimal
Ordering
+1 topic
How to order decimals from least to greatest or from greatest to least
Other Decimals
+5 topics
How to add decimals
How to convert decimals to scientific notation
How to divide decimals
How to multiply decimals
How to subtract decimals
Fractions
Complex Fractions
+5 topics
How to add complex fractions
How to divide complex fractions
How to find a complex fraction
How to multiply complex fractions
How to subtract complex fractions
Compound Fractions
+1 topic
How to find a solution to a compound fraction
Decimals with Fractions
+3 topics
How to find decimal fractions
How to find the decimal equivalent of a fraction
How to find the fractional equivalent of a decimal
Fractions and Percentage
+3 topics
How to find a fraction from a percentage
How to find fractional percentages
How to find percentage from a fraction a1
Infinite Fractions
+1 topic
How to find the amount of rational numbers between two numbers
Lowest Common Denominator
+1 topic
How to find the lowest / least common denominator
Mixed / Improper Fractions
+2 topics
How to find out a mixed fraction from an improper fraction
How to find out an improper fraction from a mixed fraction
Operations and Fractions
+4 topics
How to add fractions
How to divide fractions
How to multiply fractions
How to subtract fractions
Ordering
+1 topic
How to order fractions from least to greatest or from greatest to least
Proportion / Ratio / Rate
+6 topics
How to express a fraction as a ratio
How to find a ratio a1
How to find proportion
How to find rate
How to find the ratio of a fraction
How to find the volume of a solution
Reciprocals
+1 topic
How to find the reciprocal of a fraction
Simplifying Fractions
+1 topic
How to simplify a fraction
Whole and Part
+2 topics
How to find the part from the whole with fractions
How to find the whole from the part with fractions
Integers
Absolute Value
+1 topic
How to find absolute value
Counting
+1 topic
How to find the number of integers between two other integers
Even / Odd Numbers
+8 topics
How to add even numbers
How to add odd numbers
How to divide even numbers
How to divide odd numbers
How to multiply even numbers
How to multiply odd numbers
How to subtract even numbers
How to subtract odd numbers
Factors / Multiples
+8 topics
Greatest Common Factor
+1 topic
How to find the greatest common factor a1
Least Common Multiple
+1 topic
How to find the least common multiple
Other Factors / Multiples
+1 topic
How to factor a number
Prime Numbers
+1 topic
How to find out if a number is prime
Negative Numbers
+4 topics
How to add negative numbers
How to divide negative numbers
How to multiply negative numbers
How to subtract negative numbers
Number Line
+6 topics
Graphing an equation with a number line
+1 topic
How to graph an equation with a number line
Graphing an Inequality with a Number Line
+1 topic
How to graph an inequality with a number line
Other Number Line
+1 topic
How to find value with a number line
Operations
+4 topics
How to add integers
How to divide integers
How to multiply integers
How to subtract integers
Permutation / Combination
+2 topics
How to find permutation notation
How to find the greatest or least number of combinations
Sequences
+10 topics
Arithmetic Sequences
+5 topics
nth Term of an Arithmetic Sequence
+2 topics
How to find the next term in an arithmetic sequence
How to find the nth term of an arithmetic sequence
Other Arithmetic Sequences
+1 topic
How to find the answer to an arithmetic sequence
Common Difference in Sequences
+1 topic
How to find the common difference in sequences
Consecutive Integers
+1 topic
How to find consecutive integers
Sets
+1 topic
How to find the missing number in a set
Order of Operations
How to find order of operations
Percentage
Decimals and Percentage
+2 topics
How to find decimal equivalent to a percentage
How to find percentage equivalent to a decimal
Fractions and Percentage
+3 topics
How to find a fraction from a percentage
How to find fractional percentages
How to find percentage from a fraction
Interest
+1 topic
How to find simple interest
Other Percentage
+1 topic
How to find percentage
Percent of Change
+2 topics
How to find the percent of decrease
How to find the percent of increase
Profit Margin
+1 topic
How to find amount of profit
Sale Prices
+1 topic
How to find the sale price
Sales tax
+1 topic
How to find the amount of sales tax
Whole and Part
+2 topics
How to find the part from the whole with percentage
How to find the whole from the part with percentage
Data Analysis
Probability
Outcomes
+1 topic
How to find the probability of an outcome
Statistics
Arithmetic Mean
+1 topic
How to find arithmetic mean
Median
+1 topic
How to find median
Mode
+1 topic
How to find mode
Range
+1 topic
How to find range
Venn Diagrams
Intersection
+1 topic
How to find the intersection of a Venn Diagram
Union
+1 topic
How to find the union of a Venn Diagram
Geometry
Coordinate Geometry
Plane Geometry
Circles
+18 topics
Chords
+1 topic
How to find the length of a chord
Clock Math
+2 topics
How to find the angle of clock hands
How to find the distance between clock hands
Diameter
+2 topics
How to find the length of the diameter
How to find the ratio of diameter and circumference
Radius
+3 topics
How to find circumference
How to find the area of a circle
How to find the length of a radius
Sectors
+5 topics
How to find the angle for a percentage of a circle
How to find the angle of a sector
How to find the area of a sector
How to find the length of an arc
How to find the percentage of a sector from an angle
Hexagons
+6 topics
How to find an angle in a hexagon
How to find if hexagons are similar
How to find the area of a hexagon
How to find the length of the diagonal of a hexagon
How to find the length of the side of a hexagon
How to find the perimeter of a hexagon
Lines
+1 topic
How to find an angle of a line
Other Polygons
+5 topics
How to find an angle in a polygon
How to find the area of a polygon
How to find the length of a diagonal of a polygon
How to find the length of a side of a polygon
How to find the perimeter of a polygon
Pentagons
+5 topics
How to find an angle in a pentagon
How to find the area of a pentagon
How to find the length of the diagonal of a pentagon
How to find the length of the side of a pentagon
How to find the perimeter of a pentagon
Quadrilaterals
+44 topics
Kites
+5 topics
How to find an angle in a kite
How to find the area of a kite
How to find the length of the diagonal of a kite
How to find the length of the side of a kite
How to find the perimeter of kite
Other Quadrilaterals
+6 topics
How to find an angle in a quadrilateral
How to find if quadrilaterals are similar
How to find the area of a quadrilateral
How to find the length of the diagonal of a quadrilateral
How to find the length of the side of a quadrilateral
How to find the perimeter of a quadrilateral
Parallelograms
+5 topics
How to find an angle in a parallelogram
How to find the area of a parallelogram
How to find the length of the diagonal of a parallelogram
How to find the length of the side of a parallelogram
How to find the perimeter of a parallelogram
Rectangles
+5 topics
How to find if rectangles are similar
How to find the area of a rectangle
How to find the length of the diagonal of a rectangle
How to find the length of the side of a rectangle
How to find the perimeter of a rectangle
Rhombuses
+6 topics
How to find an angle in a rhombus
How to find if rhombuses are similar
How to find the area of a rhombus
How to find the length of the diagonal of a rhombus
How to find the length of the side of a rhombus
How to find the perimeter of a rhombus
Squares
+4 topics
How to find the area of a square
How to find the length of the diagonal of a square
How to find the length of the side of a square
How to find the perimeter of a square
Trapezoids
+6 topics
How to find an angle in a trapezoid
How to find if trapezoids are similar
How to find the area of a trapezoid
How to find the length of the diagonal of a trapezoid
How to find the length of the side of a trapezoid
How to find the perimeter of a trapezoid
Triangles
+38 topics
Acute / Obtuse Triangles
+8 topics
How to find an angle in an acute / obtuse triangle
How to find if acute / obtuse triangles are congruent
How to find if two acute / obtuse triangles are similar
How to find the area of an acute / obtuse triangle
How to find the height of an acute / obtuse triangle
How to find the length of the hypotenuse of an acute / obtuse triangle
How to find the length of the side of an acute / obtuse triangle
How to find the perimeter of an acute / obtuse triangle
Equilateral Triangles
+4 topics
How to find the area of an equilateral triangle
How to find the height of an equilateral triangle
How to find the length of the side of an equilateral triangle
How to find the perimeter of an equilateral triangle
Isosceles Triangles
+14 topics
45/45/90 Right Isosceles Triangles
+5 topics
How to find the area of a 45/45/90 right isosceles triangle
How to find the height of a 45/45/90 right isosceles triangle
How to find the length of the hypotenuse of a 45/45/90 right isosceles triangle : Pythagorean Theorem
How to find the length of the side of a 45/45/90 right isosceles triangle
How to find the perimeter of a 45/45/90 right isosceles triangle
Acute / Obtuse Isosceles Triangles
+7 topics
How to find an angle in an acute / obtuse isosceles triangle
How to find if of acute / obtuse isosceles triangle are similar
How to find if of acute / obtuse isosceles triangles are congruent
How to find the area of an acute / obtuse isosceles triangle
How to find the height of of an acute / obtuse isosceles triangle
How to find the length of the side of of an acute / obtuse isosceles triangle
How to find the perimeter of an acute / obtuse isosceles triangle
Right Triangles
+8 topics
How to find an angle in a right triangle
How to find if right triangles are congruent
How to find if right triangles are similar
How to find the area of a right triangle
How to find the height of a right triangle
How to find the length of the hypotenuse of a right triangle : Pythagorean Theorem
How to find the length of the side of a right triangle
How to find the perimeter of a right triangle
Solid Geometry
Cones
+2 topics
How to find the surface area of a cone
How to find the volume of a cone
Cubes
+4 topics
How to find the diagonal of a cube
How to find the length of an edge of a cube
How to find the surface area of a cube
How to find the volume of a cube
Cylinders
+2 topics
How to find the surface area of a cylinder
How to find the volume of a cylinder
Other Polyhedrons
+3 topics
How to find the length of an edge of a polyhedron
How to find the surface area of a polyhedron
How to find the volume of a polyhedron
Prisms
+4 topics
How to find the diagonal of a prism
How to find the length of an edge of a prism
How to find the surface area of a prism
How to find the volume of a prism
Pyramids
+3 topics
How to find the length of an edge of a pyramid
How to find the surface area of a pyramid
How to find the volume of a pyramid
Spheres
+4 topics
How to find the diameter of a sphere
How to find the radius of a sphere
How to find the surface area of a sphere
How to find the volume of a sphere
Tetrahedrons
+4 topics
How to find the diagonal of a tetrahedron
How to find the length of an edge of a tetrahedron
How to find the surface area of a tetrahedron
How to find the volume of a tetrahedron
Trigonometry
Cosine
How to find a missing side with cosine
How to find an angle with cosine
How to find negative cosine
How to find positive cosine
How to find the cosine of a missing side
How to find the cosine of an angle
How to find the domain of the cosine
How to find the period of the cosine
How to find the range of the cosine
Reference Angles
How to find a reference angle
Sine
How to find a missing side with sine
How to find an angle with sine
How to find negative sine
How to find positive sine
How to find the domain of the sine
How to find the period of the sine
How to find the range of the sine
How to find the sine of a missing side
How to find the sine of an angle
Tangent
How to find a missing side with tangent
How to find an angle with tangent
How to find negative tangent
How to find positive tangent
How to find the domain of the tangent
How to find the period of the tangent
How to find the range of the tangent
How to find the tangent for the missing side
How to find the tangent of an angle
ACT Reading
Humanities
Analyzing Authorial Tone and Method in Humanities Passages
Analyzing Sequence in Humanities Passages
Comparing and Contrasting Ideas in Humanities Passages
Determining Context-Dependent Meanings of Phrases and Clauses in Humanities Passages
Determining Context-Dependent Meanings of Words in Humanities Passages
Drawing Generalizations About Humanities Passages
Drawing Inferences from Humanities Passages
Identifying and Analyzing Important Details in Humanities Passages
Identifying and Analyzing Main Ideas in Humanities Passages
Understanding Causes and Effects in Humanities Passages
Natural Sciences
Analyzing Authorial Tone and Method in Natural Science Passages
Analyzing Sequence in Natural Science Passages
Comparing and Contrasting Ideas in Natural Science Passages
Determining Context-Dependent Meanings of Phrases and Clauses in Natural Science Passages
Determining Context-Dependent Meanings of Words in Natural Science Passages
Drawing Generalizations About Natural Science Passages
Drawing Inferences from Natural Science Passages
Identifying and Analyzing Important Details in Natural Science Passages
Identifying and Analyzing Main Ideas in Natural Science Passages
Understanding Causes and Effects in Natural Science Passages
Paired Passages
Analyzing Authorial Tone and Method in Paired Passages
Comparing and Contrasting Ideas in Paired Passages
Determining Context-Dependent Meanings of Phrases and Clauses in Paired Passages
Determining Context-Dependent Meanings of Words in Paired Passages
Identifying and Analyzing Important Details in Paired Passages
Prose Fiction
Analyzing Authorial Tone and Method in Prose Fiction Passages
Analyzing Sequence in Prose Fiction Passages
Comparing and Contrasting Ideas in Prose Fiction Passages
Determining Context-Dependent Meanings of Phrases and Clauses in Prose Fiction Passages
Determining Context-Dependent Meanings of Words in Prose Fiction Passages
Drawing Generalizations About Prose Fiction Passages
Drawing Inferences from Prose Fiction Passages
Identifying and Analyzing Important Details in Prose Fiction Passages
Identifying and Analyzing Main Ideas in Prose Fiction Passages
Understanding Causes and Effects in Prose Fiction Passages
Social Sciences / History
Analyzing Authorial Tone and Method in Social Science or History Passages
Analyzing Sequence in Social Science or History Passages
Comparing and Contrasting Ideas in Social Science or History Passages
Determining Context-Dependent Meanings of Phrases and Clauses in Social Science or History Passages
Determining Context-Dependent Meanings of Words in Social Science or History Passages
Drawing Generalizations About Social Science or History Passages
Drawing Inferences from Social Science or History Passages
Identifying and Analyzing Important Details in Social Science or History Passages
Identifying and Analyzing Main Ideas in Social Science or History Passages
Understanding Causes and Effects in Social Science or History Passages
ACT Science
Biology
How to find conflicting viewpoints in biology
How to find data representation in biology
How to find experimental design in biology
How to find research summary in biology
How to find synthesis of data in biology
Chemistry
How to find conflicting viewpoints in chemistry
How to find data representation in chemistry
How to find experimental design in chemistry
How to find research summary in chemistry
How to find synthesis of data in chemistry
Earth and Space Sciences
How to find conflicting viewpoints in earth and space sciences
How to find data representation in earth and space sciences
How to find experimental design in earth and space sciences
How to find research summary in earth and space sciences
How to find synthesis of data in earth and space sciences
Physics
How to find conflicting viewpoints in physics
How to find data representation in physics
How to find experimental design in physics
How to find research summary in physics
How to find synthesis of data in physics
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