| A | B |
|---|
| addend | a number to be added in an addition expression |
| sum | the answer to an addition problem |
| difference | the answer to a subtraction problem |
| variable | a letter that represents a number in an algebraic equation or expression |
| algebraic expression | an expression that consists of one or more variables |
| algebraic equation | a mathematical sentence that shows that two expressions have the same value |
| associative property of addition | this property states that changing the grouping of addends does not change the sum |
| commutative property of addition | this property states that changing the order of addends does not change the sum |
| identity property of addition | this property states that the sum of any number and zero is that number |
| estimate | a number close to an exact amount |
| round | to find about how many or about how much by expressing a number to the nearest ten, hundred, etc. |
