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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 5

In Exercises 5–18, solve each system by the substitution method. x + y = 4 y = 3x
Exercise 5: Solve the system of equations x + y = 4 and y = 3x using substitution.

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Start with the given system of equations: x+y=4y=3x.
Since the second equation already expresses y in terms of x as y = 3x, substitute this expression for y into the first equation.
After substitution, the first equation becomes x + 3x = 4. Combine like terms on the left side to simplify the equation.
Solve the simplified equation for x by isolating the variable.
Once you find the value of x, substitute it back into the expression y = 3x to find the corresponding value of y.

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