standard_description: Prove that, given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solutions.
problem_activity: Stage 2: Factors 1–9
Required Preparation
Materials to Gather
Paper clips
Two-color counters
Materials to Copy
Blackline Masters
Five in a Row Multiplication and Division Stage 2 Gameboard

Narrative
Students multiply using factors of 1–9. Partner A chooses two numbers and places a paper clip on each number. They multiply the numbers and place a counter on the product. Partner B moves one of the paper clips to a different number, multiplies the numbers, and places a counter on the product. Students take turns moving one paper clip, finding the product, and covering it with a counter.
Additional Information
Each group of 2 needs 25 two-color counters and 2 paper clips.


aligns: no