An integer is a whole number that can be positive, negative, or zero. Integers include all the positive whole numbers, all the negative whole numbers, and zero. In other words, integers are the set of numbers {..., -3, -2, -1, 0, 1, 2, 3, ...}.
When performing operations with integers, the following rules apply:
Adding Integers: When adding integers with the same sign, add their absolute values and keep the sign. When adding integers with different signs, subtract the smaller absolute value from the larger one and use the sign of the number with the larger absolute value.
Subtracting Integers: Subtracting an integer is the same as adding its opposite.
Multiplying and Dividing Integers: When multiplying or dividing integers, the rules for the signs are as follows:
If the signs are the same, the result is positive.
If the signs are different, the result is negative.
Absolute Value of Integers:
The absolute value of an integer is its distance from zero on the number line. The absolute value of a positive integer is the number itself, and the absolute value of a negative integer is the number without its negative sign.
Understand meanings of operations and how they relate to one another.
Understand various meanings of multiplication and division.
Identify and use relationships between operations, such as division as the inverse of multiplication, to solve problems.
Connections to the Grade 5 Focal Points (NCTM)
Algebra: Students use patterns, models, and relationships as contexts for writing and solving simple equations and inequalities. They create graphs of simple equations. They explore prime and composite numbers and discover concepts related to the addition and subtraction of fractions as they use factors and multiples, including applications of common factors and common multiples. They develop an understanding of the order of operations and use it for all operations.