Table of contents
- 0. Fundamental Concepts of Algebra3h 29m
- 1. Equations and Inequalities3h 27m
- 2. Graphs1h 43m
- 3. Functions & Graphs2h 17m
- 4. Polynomial Functions1h 54m
- 5. Rational Functions1h 23m
- 6. Exponential and Logarithmic Functions2h 28m
- 7. Measuring Angles40m
- 8. Trigonometric Functions on Right Triangles2h 5m
- 9. Unit Circle1h 19m
- 10. Graphing Trigonometric Functions1h 19m
- 11. Inverse Trigonometric Functions and Basic Trig Equations1h 41m
- 12. Trigonometric Identities 2h 34m
- 13. Non-Right Triangles1h 38m
- 14. Vectors2h 25m
- 15. Polar Equations2h 5m
- 16. Parametric Equations1h 6m
- 17. Graphing Complex Numbers1h 7m
- 18. Systems of Equations and Matrices3h 6m
- 19. Conic Sections2h 36m
- 20. Sequences, Series & Induction1h 15m
- 21. Combinatorics and Probability1h 45m
- 22. Limits & Continuity1h 49m
- 23. Intro to Derivatives & Area Under the Curve2h 9m
18. Systems of Equations and Matrices
Two Variable Systems of Linear Equations
Struggling with Precalculus?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Use the elimination method to solve the following system of linear equations.
2x+y=1
3x−y=4
A
(−1,1)
B
(1,1)
C
(1,−1)
D
(−1,−1)

1
First, write down the system of equations: 2x + y = 1 and 3x - y = 4.
To use the elimination method, add the two equations together to eliminate y. This is possible because the coefficients of y are +1 and -1.
Add the equations: (2x + y) + (3x - y) = 1 + 4. This simplifies to 5x = 5.
Solve for x by dividing both sides of the equation by 5, resulting in x = 1.
Substitute x = 1 back into one of the original equations, for example, 2x + y = 1, to find y. This gives 2(1) + y = 1, which simplifies to y = -1.
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