• Arithmetic Sequence – a list of numbers with a common difference
• Absolute Value-   The distance a number is from zero on the number line. Examples: |-4 |= 4 and |3| = 3
• Additive Inverse – Two numbers that when added together equal 0. Example, 3.2 and -3.2
• Algebraic Expression – A mathematical phrase involving at least one variable. Expressions can contain numbers and operation symbols.
• Coefficient – a number that is multiplied by the variable
• Common Difference- the amount each number in a list of numbers increases or decreases by
• Equation –   A mathematical sentence that contains an equal sign.
• Evaluate an Algebraic Expression – To perform operations to obtain a single number or value.
• Inequality – A mathematical sentence that contains the symbols >, <, ≥, or ≤.
• Inverse Operation – Pairs of operations that undo each other. Examples: Addition and subtraction are inverse operations and multiplication and division are inverse operations.
• Like Terms – Monomials that have the same variable raised to the same power. In other words, only coefficients of terms can be different.
• Linear Equation in One Variable – an equation that can be written in the form ax + b = c where a, b, and c are real numbers and a ≠ 0
• Relation – a set of ordered pairs.
• Solution –   the value or values of a variable that make an equation a true statement
• Solve – Identify the value that when substituted for the variable makes the equation a true statement.
• Variable – A letter or symbol used to represent a number.

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