In Algebra 1, students build on the skills from grade 7 involving applying the distributive property when signed numbers are involved and combining like terms. The purpose of this lesson is to revisit, refresh, and practice that grade 7 work in preparation. For example, in Algebra 1, students are expected to expand expressions like \((x+4)(x-5)\). In grade 7, they encountered expressions like \(\text-2x(x-5)\).
Lesson overview
- 9.1 Warm-up: Sorting Expressions (10 minutes)
- 9.2 Activity: Expanded Form (15 minutes)
- 9.3 Activity: Factoring and Expanding (15 minutes)
Learning goals:
- Practice expanding and factoring using the distributive property (with diagrams for support) with terms that have negative coefficients.
- Recall multiplication of positive and negative numbers.
- Rewrite subtraction expressions as adding the opposite.
Learning goals (student facing):
- Let’s work with signed numbers.
Standards:
- This lesson builds towards the standards:CCSS.HSA-SSE.A.2MS.A-SSE.2MO.A1.SSE.A.2CCSS.HSA-SSE.B.3MS.A-SSE.3MO.A1.SSE.A.3aMO.A1.SSE.A.3b
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