Subtracting by Using Addition: Mastering 2-Digit Subtraction

This video tutorial explains how to subtract two-digit numbers using addition. It begins by introducing subtraction as the opposite of addition and reviews basic subtraction concepts. The tutorial demonstrates subtraction using base ten blocks and open number lines, emphasizing the counting up method. Several examples illustrate how to rewrite subtraction problems as addition sentences, making it easier to find the difference between numbers. The video concludes with a detailed example of subtracting 86 minus 27 using the counting up method.

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