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Exercises Expressions, exponents and radicals

Example 7.43 from Prealgebra, 7.4 Properties of Identity, Inverses, and Zero

Properties of Identity, Inverses, and Zero: example 7.43

Simplify: $6 x + 12$

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
We cannot combine the terms in parentheses, so we multiply the two fractions first.

$\frac{3}{4} \cdot \frac{4}{3} (6 x + 12)$

Multiply; the product of reciprocals is 1. $1 (6 x + 12)$

Simplify by recognizing the multiplicative identity. $6 x + 12$

Your turn

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

Simplify: $\frac{2}{5} \cdot \frac{5}{2} (20 y + 50) .$

How did it go?

PreviousProperties of Identity, Inverses, and Zero: example 7.42 Next Systems of Measurement: example 7.44

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.