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 binomials
Multiplying binomials
Multiplying binomials
Sal expresses the product (3x+2)(5x-7) as 15x²-11x-14.
License: CC BY-NC-SA by Khan Academy