Lesson 4: Solving Systems by Elimination

• How do we solve a system by elimination?
• Why do we multiply equations?
• What are we trying to eliminate?
• How do we find both variables?

Elimination, opposite coefficients, multiply, add, subtract, eliminate

CCSS.MATH.8.EE.C.8

Description: Students solve systems by making one variable's coefficients opposite, then adding or subtracting the equations to eliminate that variable. This creates one equation with one variable. Step-by-step guides help them follow the process. Purpose: To develop procedural fluency in an algebraic method for solving systems. DOK Level: 2-3 (Application)

• Start with ready-to-eliminate systems: Opposite coefficients already present
• For struggling learners: Multiply only one equation; use simple multipliers
• For advanced learners: Multiply both equations to create opposite coefficients
• Step-by-step cards: Provide elimination steps in ord

• Observation: Do students identify opposite coefficients?

• Worksheet: Solve 4 systems using elimination

• Ready-to-eliminate first: Practice when coefficients are already opposite

• Verification: Check solutions in both equations

• Elimination method step-by-step guides

• Ready-to-eliminate practice worksheets

• Full elimination practice worksheets

• Verification worksheets

• Anchor chart for elimination steps

• Resource: Khan Academy "Solving Systems by Elimination" (adapted)