![]() The commutative property applies to addition, but not to subtraction. Essentially, this property is true for operations where the values can move around, “commute”, and the outcome of the expression or equation will not change. The technical term for this quality is known as the commutative property. We can see that the order matters when dealing with a situation involving subtraction. However, the same is not true for subtraction. The placement, or arrangement of the values has no effect on the outcome. It is important to notice that when using addition, the order of the values does not matter. So in this example we would be starting at 6, and jumping 4 units to the right. Each jump to the right represents the addition of one unit. On a number line, addition is represented by jumps to the right, in the positive direction. You had 6 bags initially, and then “combined” that amount with 4 more bags. This situation can be described using the equation \(6+4=10\). How many bags of popcorn do you now have available to sell? For this scenario, since we are looking at an increase of bags, we will use addition. You need to replenish your stock in order to keep up your sales, so you make 4 more bags of popcorn. Now, let’s say you started with 20 bags of popcorn and ended up with 6 bags left at the end of the day. Each jump backward represents subtraction by 1. On a number line, we can represent this deduction by starting at 20 and then moving backward four units in the negative direction. ![]() Our subtraction equation is written as \(20-4=16\). ![]() We started with 20 bags, and we “decreased by 4,” or subtracted 4. We can represent this situation with a simple equation that involves subtraction. This means that your remaining number of bags will decrease. When your first customer arrives, they wish to purchase 4 bags of popcorn. For this scenario, let’s assume that you are trying to raise money by selling bags of popcorn, and you start with 20 bags. Let’s imagine a situation that involves the sale of popcorn. We will use a number line to illustrate the following examples. ![]() One strategy for visualizing these two operations is to use a number line. One adds value, and the other deducts value. The answer to a subtraction problem is called the differenceĮssentially, addition and subtraction are opposite operations.The symbol we use for subtraction is \(–\).The answer to an addition problem is called the sum.The symbol we use for addition is \(+\). ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |