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Exercises Expressions, exponents and radicals

Example 7.10 from Prealgebra, 7.2 Commutative and Associative Properties

Commutative and Associative Properties: example 7.10

Simplify: $−84 n + (−73 n) + 84 n .$

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
Notice the first and third terms are opposites, so we can use the commutative property of addition to reorder the terms.

$−84 n + (−73 n) + 84 n$

Re-order the terms. $−84 n + 84 n + (−73 n)$

Add left to right. $0 + (−73 n)$

Add. $−73 n$

Your turn

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

Simplify: $−27 a + (−48 a) + 27 a .$

How did it go?

PreviousCommutative and Associative Properties: example 7.9 Next Commutative and Associative Properties: example 7.11

From Prealgebra (1st edition) by OpenStax (Rice University), section 7.2, 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.