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Ch. 1 - Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 94

In Exercises 91–100, find all values of x satisfying the given conditions. y=x−x−2andy=4y = x - \(\sqrt{x - 2}\) \(\quad\) \(\text{and}\) \(\quad\) y = 4

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Start with the given system of equations: \(y = x - \sqrt{x - 2}\) and \(y = 4\).
Since both expressions equal \(y\), set them equal to each other: \(4 = x - \sqrt{x - 2}\).
Isolate the square root term: \(\sqrt{x - 2} = x - 4\).
Square both sides to eliminate the square root: \((\sqrt{x - 2})^2 = (x - 4)^2\), which simplifies to \(x - 2 = (x - 4)^2\).
Expand the right side and rearrange the equation to form a quadratic: \(x - 2 = x^2 - 8x + 16\), then bring all terms to one side to get \(0 = x^2 - 9x + 18\).

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