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Exercises Numbers, fractions and percents

Example 3.42 from Prealgebra, 3.3 Subtract Integers

Subtract Integers: example 3.42

Evaluate $20 - z when$

ⓐ $z = 12$
ⓑ $z = - 12$

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
ⓐ To evaluate $20 - z when z = 12,$ substitute $12$ for $z$ in the expression.

Subtract.

ⓑ To evaluate $20 - z when z = −12, substitute −12 for z in the expression.$

Subtract.

Your turn

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

Evaluate each expression:

$17 - k when$

ⓐ $k = 19$
ⓑ $k = −19$

How did it go?

PreviousSubtract Integers: example 3.41 Next Subtract Integers: example 3.43

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.