ACT Math Preparation Vocabulary

Vocabulary flashcards generated from ACT math review notes covering algebra formulas, rules, and shortcut simplifications.

Parallel Lines

Lines that have the same slope.

Perpendicular Slopes

Slopes that are negative reciprocals of each other.

Zero Exponent Rule

Any non-zero base raised to the power of zero always equals $1$ ($a^0 = 1$).

ACT Radical Shortcuts

Common simplified radicals to memorize: $\sqrt{8} = 2\sqrt{2}$, $\sqrt{12} = 2\sqrt{3}$, $\sqrt{18} = 3\sqrt{2}$, $\sqrt{27} = 3\sqrt{3}$, $\sqrt{32} = 4\sqrt{2}$, and $\sqrt{75} = 5\sqrt{3}$.

Standard Form of a Quadratic

The standard form equation written as $ax^2 + bx + c$.

Quadratic Formula

The formula used to find solutions to a quadratic equation: $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$.

Discriminant

The expression $b^2 - 4ac$ inside the quadratic formula used to determine the number and type of solutions.

Positive Discriminant

Indicates that a quadratic equation has $2$ real solutions.

Zero Discriminant

Indicates that a quadratic equation has $1$ solution.

Negative Discriminant

Indicates that a quadratic equation has no real solution.

Difference of Squares

An expression in the form $a^2 - b^2$ which always factors into $(a - b)(a + b)$.

Direct Variation

A relationship expressed by $y = kx$, where $y$ increases as $x$ increases.

Inverse Variation

A relationship expressed by $y = \frac{k}{x}$, where $y$ decreases as $x$ increases.

Distance Formula (Word Problems)

The relation $d = R(T)$, where distance equals rate multiplied by time.

Interest Formula

The equation $I = Prt$, representing simple interest.

Parallel Lines in Systems of Equations

A system representing parallel lines has NO SOLUTIONS because the lines do not intersect.

Absolute Value

The distance of a number from $0$.