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Numerial expression

a numerical expression consists of numbers and operations 3+5

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Variable

a variable is a letter used to represent one or more numbers. x=6

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variable expression

a variable expression consists of numbers, variables, and operations 7+3+4x

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Evaluate a variable expression

to evaluate a variable expression, substitute a number for each variable and evaluate the resulting numerical expression

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verbal model

a verbal model describes a problem using words as labels and using math symbols to relate the words

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Associative property of addition

(3 +2) 4 = 3+ (2 +4)

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Identity property of addition

0 + b = b

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Identity property of multiplication

1(-7) = -7

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commutative property of multiplication

cd=dc

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Equivalent numerical expressions

numerical expressions that have the same value

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equivalent variable expressions

equivalent variable expressions have the same value for all values of the variable(s)

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Terms of an expression

The parts of an expression that are added together are called terms 4y, -6. 3y

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Like terms

like terms are terms that have identical variable parts 4y and 3y

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Coefficient of terms

The coefficient of a term with a variable is the number parts of the term 4, 3

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Constant term

A constant term has a number but no variable -6

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Equation

an equation is a mathematical sentence formed by placing an equal sign, = between two expressions x +3 = 7

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Solution of an equation

a solution of an equation with a variable is a number that produces a true statement when it is substituted for the variable. x + 2 = 4

2+2 = 4

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Solving an equation

finding all solutions of an equation is called solving the equation

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Inverse operations

Inverse operations are two operations that undo each other, such as addition and subtraction

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Equivalent equations

Equivalent equations are equations that have the same solutions(s)

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