How Do You Master Subtraction Facts In Arithmetic Using Complements?
Subtraction is the process of calculating the difference between two numbers. To be able to subtract well, one must first master “addition facts” that consist of all possibilities of the sums of one-digit numbers; i.e., 1 + 1, 1 + 2, …, 9 + 9 (refer to additional resources). This article will teach you how to master the basic subtraction facts using complements. By using complements, we will be able to find the difference between some numbers by adding! You say, “What?” Read on. Like the addition table, we can create a corresponding subtraction table. If you know the 45 addition facts (see additional resources), then mastery of subtraction facts is as easy as “adding 1, 2, 3.” The numbers at the left side of the table represent the minuends (top number), and the numbers across the top of the table, the subtrahends (bottom number). The numbers within the table are the differences (or remainders, or balances). Note the patterned structure of the table. Carefully inspect the table in St
