Khan Academy (English - US curriculum)
Math by grade
Eureka Math/EngageNY
Algebra 1 (Eureka Math/EngageNY)
Module 1: Relationships between quantities and reasoning with equations and their graphs
Topic B: Lesson 9: Multiplying monomials by polynomials
Multiplying monomials by polynomials
Multiplying monomials by polynomials
Sal multiplies -4x² by (3x² \+ 25x - 7).
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