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Exercises Roots and quadratic equations

Example 10.18 from Elementary Algebra, 10.2 Solve Quadratic Equations by Completing the Square

Solve Quadratic Equations by Completing the Square: example 10.18

Solve $x^{2} + 8 x = 48$ by completing the square.

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

Your turn

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

Solve $c^{2} + 4 c = 5$ by completing the square.

How did it go?

PreviousSolve Quadratic Equations by Completing the Square: example 10.17 Next Solve Quadratic Equations by Completing the Square: example 10.19

From Elementary Algebra (1st edition) by OpenStax (Rice University), section 10.2, 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.