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subtract 27
To "undo" add 27, I would...
subtract 4
To "undo" add 4, I would...
To "undo" subtract 65, I would...
To "undo" subtract 37, I would...
divide by 10
To "undo" multiply by 10, I would...
divide by 7
To "undo" multiply by 7, I would...
multiply by 9
To "undo" divide by 9, I would...
multiply by 23
to "undo" divide by 23, I would...
Equation
A mathematical sentence that contains an equals sign
Variable
an alphabetic character representing a number, called the value, which is either arbitrary or not fully specified or unknown. It is usually a letter like x or y.
equivalent
Equal to
inverse operation
Operations that undo each other
Subtraction
to take a quantity away from another
to join two or more quantities
Division
process of breaking a quantity into equal parts
Multiplication
inequality
A mathematical sentence that shows the relationship between quantities that are not equivalent
<
Less than
>
Greater than
Less than or equal to
Greater than or equal to
Not equal to
x+9-9
x+9
x-7+7
x-7
-7
What is the inverse of +7?
plus 15
What is the inverse of minus 15?
divide by 6
What is the inverse of times 6?
minus 4
What is the inverse of plus 4?
times 3
What is the inverse of divided by 3?
undoes the given operation
What does the inverse operation do?
to undo negative 19
to undo negative 225
divide 500
to undo 500
divide 9,000
to undo 9,000
multiply 5
to undo 5
multiply 9,000,000
to undo 9,000,000