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Exercises Expressions, exponents and radicals

Example 2.22 from Prealgebra, 2.2 Evaluate, Simplify, and Translate Expressions

Evaluate, Simplify, and Translate Expressions: example 2.22

Simplify the expression: $7 x^{2} + 8 x + x^{2} + 4 x .$

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

Identify the like terms.

Rearrange the expression so like terms are together.

Add the coefficients of the like terms.

These are not like terms and cannot be combined. So $8 x^{2} + 12 x$ is in simplest form.

Your turn

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

Simplify:

$3 x^{2} + 9 x + x^{2} + 5 x$

How did it go?

PreviousEvaluate, Simplify, and Translate Expressions: example 2.21 Next Evaluate, Simplify, and Translate Expressions: example 2.23

From Prealgebra (1st edition) by OpenStax (Rice University), section 2.2, 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.