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Exercises Numbers, fractions and percents

Example 4.100 from Prealgebra, 4.7 Solve Equations with Fractions

Solve Equations with Fractions: example 4.100

Solve: $\frac{p}{−8} = −40 .$

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
Here, $p$ is divided by $−8 .$ We must multiply by $\frac{c}{−7} = −35 .$ to isolate $p .$

Multiply both sides by $−8$

Multiply.

Simplify.

Check:

Substitute $p = 320$ .

The equation is true.

Your turn

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

Solve: $\frac{c}{−7} = −35 .$

How did it go?

PreviousSolve Equations with Fractions: example 4.99 Next Solve Equations with Fractions: example 4.101

From Prealgebra (1st edition) by OpenStax (Rice University), section 4.7, 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.