# Unit 3 Key Terms

• Algebraic Expression: An expression involving at least one variable and sometimes numbers and operation symbols.
• Associative Property of Addition: The sum of a set of numbers is the same no matter how the numbers are grouped. a + (b + c) = (a + b) + c
• Associative Property of Multiplication: The product of a set of numbers is the same no matter how the numbers are grouped. a(bc)=(ab)c
• Coefficient: A number multiplied by a variable in an algebraic expression.
• Commutative Property of Addition: The sum of a group of numbers is the same regardless of the order in which the numbers are arranged.   a + b   = b + a
• Commutative Property of Multiplication: The product of a group of numbers is the same regardless of the order in which the numbers are arranged. ab = ba
• Constant: A quantity that does not change its value.
• Distributive Property: If you multiply a sum by a number, you will get the same result if you multiply each addend by that number and add the products.   a(b+c)=ab+ac
• Exponent: The number of times a number or expression (called base) is used as a factor of repeated multiplication. Also called the power.
• Term: A number, a variable, or a product of numbers and variables.
• Like Terms: Terms in an algebraic expression that have the same variable raised to the same power. Only the coefficients of like terms are different.
• Order of Operations: The rules to be followed when simplifying expressions.
• Variable: A letter or symbol used to represent a number or quantities that vary.

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