Subtraction
Subtraction is the process of taking one number away from another. It is essentially the opposite of addition. When you subtract, you are finding the difference between two numbers.
Subtraction Notation
Subtraction is denoted by the minus sign (-). For example, in the expression 9 - 5, 9 is the minuend, 5 is the subtrahend, and 4 is the difference.
Subtraction Properties
There are a few important properties of subtraction:
- Commutative Property: The order in which numbers are subtracted does not affect the result. For example, 7 - 3 = 4 is the same as 3 - 7 = -4.
- Associative Property: The grouping of the numbers being subtracted does not affect the result. For example, (8 - 5) - 3 = 8 - (5 - 3) = 3.
- Identity Property: When you subtract 0 from a number, the result is the number itself. For example, 9 - 0 = 9.
Subtraction Strategies
There are various strategies for performing subtraction, including:
- Counting Back: Starting from the larger number and counting back the smaller number to find the difference.
- Number Line: Using a number line to visually represent the subtraction process.
- Regrouping: When the subtrahend is larger than the minuend, regrouping or borrowing is used to perform the subtraction.
Practice Problems
Now that we've covered the basics of subtraction, let's try some practice problems:
- Calculate the difference: 15 - 7 = ?
- Find the result of: 24 - 15 = ?
- Determine the value of: 39 - 11 = ?
Once you have practiced these problems, you should have a good understanding of subtraction. Remember to review the subtraction properties and strategies to further reinforce your understanding.
Happy subtracting!
[Subtraction] Related Worksheets and Study Guides:
.◂Math Worksheets and Study Guides Seventh Grade. Measurement, Perimeter, and Circumference
Study Guide
Measurement, Perimeter, and Circumference 
Worksheet/Answer key
Measurement, Perimeter, and Circumference Worksheet/Answer key
Measurement, Perimeter, and Circumference Worksheet/Answer key
Measurement, Perimeter, and Circumference
Worksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyThe resources above cover the following skills:
Geometry (NCTM)
Use visualization, spatial reasoning, and geometric modeling to solve problems.
Use geometric models to represent and explain numerical and algebraic relationships.
Measurement (NCTM)
Apply appropriate techniques, tools, and formulas to determine measurements.
Select and apply techniques and tools to accurately find length, area, volume, and angle measures to appropriate levels of precision.
Develop and use formulas to determine the circumference of circles and the area of triangles, parallelograms, trapezoids, and circles and develop strategies to find the area of more-complex shapes.
Connections to the Grade 7 Focal Points (NCTM)
Measurement and Geometry: Students connect their work on proportionality with their work on area and volume by investigating similar objects. They understand that if a scale factor describes how corresponding lengths in two similar objects are related, then the square of the scale factor describes how corresponding areas are related, and the cube of the scale factor describes how corresponding volumes are related. Students apply their work on proportionality to measurement in different contexts, including converting among different units of measurement to solve problems involving rates such as motion at a constant speed. They also apply proportionality when they work with the circumference, radius, and diameter of a circle; when they find the area of a sector of a circle; and when they make scale drawings.