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Exercises Numbers, fractions and percents

Example 3.37 from Prealgebra, 3.3 Subtract Integers

Subtract Integers: example 3.37

Simplify:

ⓐ $9 - (−15) and 9 + 15$
ⓑ $−7 - (−4) and −7 + 4$

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

ⓐ

$9 - (−15)$ and $9 + 15$

Subtract to simplify. $9 - (−15) = 24$

Add to simplify. $9 + 15 = 24$

Subtracting −15 from 9 is the same as adding 15 to 9.

ⓑ

$−7 - (−4)$ and $−7 + 4$

Subtract to simplify. $−7 - (−4) = −3$

Add to simplify. $−7 + 4 = −3$

Subtracting −4 from −7 is the same as adding 4 to −7

Your turn

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

Simplify each expression:

ⓐ $6 - (−13) and 6 + 13$
ⓑ $−5 - (−1) and −5 + 1$

How did it go?

PreviousSubtract Integers: example 3.36 Next Subtract Integers: example 3.38

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.