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variable expression

an expression that contains a variable (a symbol used to represent one or more numbers)

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numeric expression

an expression, such as 4.50 x 4, that names a particular number

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simplifying expression

replacing a numerical expression by the simplest name for its value

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grouping symbols

a device, such as a pair of parentheses, used to enclose an expression that should be simplified first.

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equation

formed by placing equals sign between two numerical or variable expressions, called the sides of the equation

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open sentence

sentences containing variables (like the equations 5x - 1 = 9 and y + 2 = 2 + y)

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domain

the given set of numbers that a variable can represent

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solution / root

any value of a variable that turns an open sentence into a true statement

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sum / difference / product / quotient

addition / subtraction / multiplication / division

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real numbers

any number that is either positive, negative, or zero

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integers

positive integers, negative integers, and zero

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whole numbers

zero and all positive integers

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inequality symbols

used to show the order of two real numbers (< less than, > greater than)

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opposite

each number in a pair such as 4 and -4

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absolute value

the positive number of any pair of opposite non-zero real numbers is called the absolute value of each number in the pair

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solution set

the set of all solutions of an open sentence

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