Table of contents
- 0. Review of Algebra4h 18m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations1h 43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 5m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 22m
- 10. Combinatorics & Probability1h 45m
7. Systems of Equations & Matrices
Two Variable Systems of Linear Equations
Problem 29
Textbook Question
In Exercises 19–30, solve each system by the addition method. 3x = 4y + 1 3y = 1 - 4x

Verified step by step guidance1
Rewrite both equations in standard form (Ax + By = C) to prepare for the addition method. For the first equation, subtract 4y and 1 from both sides to get . For the second equation, add 4x to both sides and subtract 1 from both sides to get .
Align the two equations for addition: and .
Multiply each equation by a suitable number so that the coefficients of either or are opposites. For example, multiply the first equation by 3 and the second equation by 4 to align the coefficients of : and .
Add the two resulting equations to eliminate . This will give you an equation with only . Solve this equation for .
Substitute the value of back into one of the original equations to solve for . This completes the solution to the system.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
System of Linear Equations
A system of linear equations consists of two or more linear equations with the same set of variables. The solution is the set of variable values that satisfy all equations simultaneously. Understanding how to interpret and manipulate these equations is essential for solving the system.
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Addition Method (Elimination Method)
The addition method involves adding or subtracting equations to eliminate one variable, making it easier to solve for the remaining variable. This method requires aligning terms and possibly multiplying equations to create opposite coefficients for one variable.
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Rearranging Equations
Before applying the addition method, equations often need to be rearranged into standard form (Ax + By = C). This makes it easier to identify coefficients and perform elimination. Rearranging involves moving all terms to one side and simplifying.
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Related Practice
Textbook Question
Solve each system by elimination. In systems with fractions, first clear denominators. See Example 2.6x + 7y + 2 = 07x - 6y - 26 = 0
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