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Ch. 5 - Systems of Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 6, Problema 7

In Exercises 5–18, solve each system by the substitution method. {x+3y=8y=2x−9\(\begin{cases}\) x + 3y = 8 \\ y = 2x - 9 \(\end{cases}\)

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Identify the system of equations: \(\begin{cases} x + 3y = 8 \\ y = 2x - 9 \end{cases}\).
Since the second equation is already solved for \(y\), substitute \(y = 2x - 9\) into the first equation.
Replace \(y\) in the first equation: \(x + 3(2x - 9) = 8\).
Simplify and solve the resulting equation for \(x\): \(x + 6x - 27 = 8\).
Once you find \(x\), substitute it back into \(y = 2x - 9\) to find the value of \(y\).

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