🔟elementary algebra review

key term - Elimination Method

Definition

The elimination method is a technique used to solve systems of linear equations by eliminating one of the variables through addition or subtraction of the equations. This method allows for the determination of the values of the variables that satisfy all the equations in the system.

5 Must Know Facts For Your Next Test

  1. The elimination method involves adding or subtracting the equations in a system to eliminate one of the variables, allowing you to solve for the remaining variable.
  2. To use the elimination method, the coefficients of the variable to be eliminated must be opposite in sign and the same in absolute value.
  3. The elimination method can be used to solve both 2x2 and 3x3 systems of linear equations.
  4. Applying the elimination method to solve a system of equations can lead to the determination of a unique solution, no solution, or infinitely many solutions.
  5. The elimination method is often preferred over the substitution method when the coefficients of the variables are large or the equations are more complex.

Review Questions

  • Explain the process of using the elimination method to solve a system of two linear equations with two variables.
    • To solve a system of two linear equations with two variables using the elimination method, you first need to identify the variable you want to eliminate. This is typically done by looking at the coefficients of the variables in each equation. You then add or subtract the equations to eliminate one of the variables, leaving you with a single equation in one variable. Once you have solved for that variable, you can substitute its value back into one of the original equations to find the value of the other variable. This process allows you to determine the unique solution that satisfies both equations in the system.
  • Describe how the elimination method can be used to solve a system of three linear equations with three variables.
    • To solve a system of three linear equations with three variables using the elimination method, you first need to eliminate one variable by adding or subtracting the equations. This will leave you with a system of two equations in two variables. You can then use the elimination method again to eliminate one of the remaining variables, resulting in a single equation in one variable. Once you have solved for that variable, you can substitute its value back into one of the original equations to find the value of the second variable. Finally, you can substitute the values of the first two variables into the remaining equation to solve for the third variable. This step-by-step process allows you to determine the unique solution that satisfies all three equations in the system.
  • Analyze the advantages and limitations of the elimination method compared to other techniques for solving systems of equations, such as the substitution method.
    • The elimination method is often preferred over the substitution method when the coefficients of the variables are large or the equations are more complex, as it can be easier to work with. Additionally, the elimination method can be applied to both 2x2 and 3x3 systems of linear equations, making it a versatile technique. However, the elimination method does have some limitations. It requires that the coefficients of the variable to be eliminated have opposite signs and the same absolute value, which may not always be the case. In situations where this condition is not met, the substitution method may be more appropriate. Furthermore, the elimination method can be more time-consuming and prone to errors, especially when dealing with larger systems of equations. Therefore, the choice between the elimination method and other techniques, such as substitution, depends on the specific characteristics of the system of equations being solved.