Lesson objective: Fluently multiply with negative numbers.

This lesson helps to build fluency with multiplication of rational numbers. Number lines are used here so students can build on their prior knowledge of representing opposites, addition, and subtraction on the number line. By representing multiplication on the number line, students will see the sign rules for multiplication as a logical extension of this prior knowledge. This work develops students' understanding that they can represent multiplication with negative numbers on the number line and that there are patterns or "sign rules" for multiplying with negative numbers.

Students engage in Mathematical Practice 7 (Look for and make use of structure) as they extend their knowledge of the number line to include multiplying with negative numbers and notice patterns in their work.

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