Explore the Lesson


A. Comparing Solution Strategies

This Unit has explored three methods of solving a system of linear equations: graphing, substitution, and elimination. Each of the three methods can be used to solve any linear system, but sometimes one method is preferable to the others. Compare your responses in the Warm Up to the following table.

Strategy Good to use when Best to avoid when
Graphing

  • something visual is desired

  • graphing technology is available

  • a quick verification is desired

  • an exact solution is desired

Substitution

  • one variable is isolated or easy to isolate

  • isolating a variable produces a complex expression

Elimination

  • one variable has the same coefficient in each of the equations

  • a complicated LCM is required to give a variable in each equation the same coefficient

 

Choosing the most appropriate method can save you effort. After solving a system, another method can also be used to verify the solution.