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Exercises Roots and quadratic equations

Example 9.76 from Elementary Algebra, 9.6 Solve Equations with Square Roots

Solve Equations with Square Roots: example 9.76

Solve: $\sqrt{5 n - 4} - 9 = 0$ .

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 isolate the radical, add 9 to both sides.

Simplify.

Square both sides of the equation.

Solve the new equation.

Check the answer.

The solution is n = 17.

Your turn

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

Solve: $\sqrt{3 m + 2} - 5 = 0$ .

How did it go?

PreviousSolve Equations with Square Roots: example 9.75 Next Solve Equations with Square Roots: example 9.77

From Elementary Algebra (1st edition) by OpenStax (Rice University), section 9.6, 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.