2.3.6 Lesson Summary

In this lesson, you learned how to:

• Solve systems of equations by substituting a variable or an expression.
• Identify more than one way to perform a substitution and decide how to substitute based on how the given equations are written.

Here are the activities that helped you reach those goals:

• 2.3.1: Finding Connections between Graphs and Equations
  • In this activity, you analyzed the relationship between systems of equations and their graphs. You determined whether a given graph could represent a specific system of equations using your knowledge of horizontal and vertical lines and the slopes and intercepts of those lines.
• 2.3.2: Checking Solutions in Systems
  • In this activity, you solved different systems of equations using any method available and then checked your solution by substituting the values found back into the original equations to verify their accuracy.
  • 2.3.2: Self Check
  • 2.3.2: Additional Resources
• 2.3.3: Solving Equations Using Substitution
  • In this activity, you used the substitution method to solve systems of equations. By isolating a variable in one of the equations, you found an equivalent expression that was substituted into the second equation. Using this method, the solution to one variable was found. This value was then substituted back into the first equation to find the value of the remaining unknown variable
  • 2.3.3: Self Check
  • 2.3.3: Additional Resources
• 2.3.4: Solving More Equations
  • In this activity, you continued to solve systems of equations using substitution, but you went a step further by showing your reasoning for each step in the process.

After these activities, you completed the following practice.

• 2.3.5: Practice