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Exercises Expressions, exponents and radicals

Example 7.16 from Prealgebra, 7.2 Commutative and Associative Properties

Commutative and Associative Properties: example 7.16

Simplify: $18 p + 6 q + (−15 p) + 5 q .$

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
Use the Commutative Property of Addition to re-order so that like terms are together.

$18 p + 6 q + (−15 p) + 5 q$

Re-order terms. $18 p + (−15 p) + 6 q + 5 q$

Combine like terms. $3 p + 11 q$

Your turn

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

Simplify: $23 r + 14 s + 9 r + (−15 s) .$

How did it go?

PreviousCommutative and Associative Properties: example 7.15 Next Distributive Property: example 7.17

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.