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Exercises Numbers, fractions and percents

Example 3.36 from Prealgebra, 3.3 Subtract Integers

Subtract Integers: example 3.36

Simplify:

ⓐ $13 - 8 and 13 + (−8)$
ⓑ $−17 - 9 and −17 + (−9)$

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution

ⓐ

$13 - 8$ and $13 + (−8)$

Subtract to simplify. $13 - 8 = 5$

Add to simplify. $13 + (−8) = 5$

Subtracting 8 from 13 is the same as adding −8 to 13.

ⓑ

$−17 - 9$ and $−17 + (−9)$

Subtract to simplify. $−17 - 9 = −26$

Add to simplify. $−17 + (−9) = −26$

Subtracting 9 from −17 is the same as adding −9 to −17.

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Simplify each expression:

ⓐ $21 - 13 and 21 + (−13)$
ⓑ $−11 - 7 and −11 + (−7)$

How did it go?

PreviousSubtract Integers: example 3.35 Next Subtract Integers: example 3.37

From Prealgebra (1st edition) by OpenStax (Rice University), section 3.3, licensed under CC BY 4.0. Original at openstax.org. We split the solution into steps; the words, numbers and figures are the book's. OpenStax doesn't endorse this site.