The expression is 

Additive inverse of – 8 is 8.

To subtract – 8, add 8.

Now, the expression becomes .

To add integers first draw a number line diagram.

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• Start from zero move 5 units left to reach .
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• Then move 8 units right show the addition of 8.
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• Find the final position on the number line.
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The difference of is .

The difference of is .