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Exercises Expressions, exponents and radicals

Example 7.39 from Prealgebra, 7.4 Properties of Identity, Inverses, and Zero

Properties of Identity, Inverses, and Zero: example 7.39

Simplify: $−12 z + 9 + 12 z .$

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

$3 x + 15 - 3 x$

Notice the additive inverses, $3 x$ and $−3 x$ . $0 + 15$

Add. $15$

Your turn

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

Simplify: $−12 z + 9 + 12 z .$

How did it go?

PreviousProperties of Identity, Inverses, and Zero: example 7.38 Next Properties of Identity, Inverses, and Zero: example 7.40

From Prealgebra (1st edition) by OpenStax (Rice University), section 7.4, 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.