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Exercises Numbers, fractions and percents

Example 5.40 from Prealgebra, 5.4 Solve Equations with Decimals

Solve Equations with Decimals: example 5.40

Determine whether each of the following is a solution of $x - 0.7 = 1.5 :$

ⓐ $x = 1$ ⓑ $x = −0.8$ ⓒ $x = 2.2$

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

ⓐ

Subtract.

Since $x = 1$ does not result in a true equation, $1$ is not a solution to the equation.

ⓑ

Subtract.

Since $x = −0.8$ does not result in a true equation, $−0.8$ is not a solution to the equation.

ⓒ

Subtract.

Since $x = 2.2$ results in a true equation, $2.2$ is a solution to the equation.

Your turn

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

Determine whether each value is a solution of the given equation.

$x - 0.6 = 1.3 :$ ⓐ $x = 0.7$ ⓑ $x = 1.9$ ⓒ $x = −0.7$

How did it go?

PreviousDecimals and Fractions: example 5.39 Next Solve Equations with Decimals: example 5.41

From Prealgebra (1st edition) by OpenStax (Rice University), section 5.4, 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.