Solve a system of equations! Elimination method, (LCM method) | Summary and Q&A

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June 13, 2016
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Solve a system of equations! Elimination method, (LCM method)

TL;DR

This video explains how to solve a system of equations using the elimination method.

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Q: How does the elimination method work when solving systems of equations?

The elimination method involves adding or subtracting equations in order to eliminate one variable and find the value of the other variable. By manipulating the equations, the variables can be eliminated through careful coefficient matching.

Q: Why is finding the LCM important in the elimination method?

Finding the LCM helps in creating equivalent equations with matching coefficients for the variable to be eliminated. It ensures that both equations can be combined without altering the overall solution.

Q: What should be done if both equations have the same sign for the coefficient of the variable being eliminated?

If both equations have the same sign for the coefficient of the variable being eliminated, one equation should be multiplied by a factor that will make the coefficients opposite in sign. This allows for their cancellation during the addition or subtraction step.

Q: How is the solution represented for a system of equations?

The solution is typically represented as an ordered pair (x, y), where x represents the value of one variable and y represents the value of the other variable. This ordered pair satisfies both equations in the system.

Summary & Key Takeaways

• The video demonstrates how to solve a system of equations with the elimination method by finding the lowest common multiple (LCM) of the coefficients.

• By multiplying one equation by a factor that will make the coefficients of one variable opposite in sign, the equations can be added to eliminate that variable.

• After eliminating one variable, the remaining equation can be solved to find the value of the other variable.