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Example1

Title: Subtracting signed numbers

Grade 6+ Lesson s1-l3

Explanation: The best way to understand algebra is by looking at some examples. Take turns and read each example for easy understanding.

Examples

Topics → Definition Example1 Example2

Subtract 7 from 12.

Step 1

Subtracting a number is the same as adding its opposite:

12 − 7 = 12 + (−7)

Explanation:

Here, we rewrite as the addition of the opposite.

Step 2

When signs are different, subtract the smaller absolute value from the larger absolute value, and keep the sign of the larger number:

\$\∣12\∣=12\$

\$\∣−7\∣=7 \$

12 + (−7) = 5

So, the answer is 5.

Explanation:

Here, we apply the rule for adding signed numbers, and then we get the answer of 5.