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Ch. 5 - Systems of Equations and Inequalities
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Not the one you use?Change textbook
Chapter 6, Problem 17

Solve each system in Exercises 5–18. {3(2x+y)+5z=12(x3y+4z)=94(1+x)=3(z3y)\(\begin{cases}\)3(2x + y) + 5z = -1 \\2(x - 3y + 4z) = -9 \\4(1 + x) = -3(z - 3y)\(\end{cases}\)

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First, write down the given system of equations clearly: \(3(2x + y) + 5z = -1\) \(2(x - 3y + 4z) = -9\) \(4(1 + x) = -3(z - 3y)\)
Next, simplify each equation by distributing the constants inside the parentheses: For the first equation: \(3 \times 2x + 3 \times y + 5z = -1\) which simplifies to \(6x + 3y + 5z = -1\). For the second equation: \(2 \times x - 2 \times 3y + 2 \times 4z = -9\) which simplifies to \(2x - 6y + 8z = -9\). For the third equation: \(4 \times 1 + 4 \times x = -3 \times z + 3 \times 3y\) which simplifies to \(4 + 4x = -3z + 9y\).
Rearrange the third equation to bring all terms to one side, making it consistent with the others: \(4x - 9y + 3z = -4\)
Now, write the simplified system of linear equations: \(6x + 3y + 5z = -1\) \(2x - 6y + 8z = -9\) \(4x - 9y + 3z = -4\)
To solve the system, choose a method such as substitution, elimination, or matrix methods (like Gaussian elimination). For example, you can: - Use elimination to eliminate one variable between two equations, - Then solve the resulting two-variable system, - Substitute back to find the third variable.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Systems of Linear Equations

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