Khan Academy (English - US curriculum)
Math by grade
Eureka Math/EngageNY
Algebra 1 (Eureka Math/EngageNY)
Module 4: Polynomial and quadratic expressions, equations, and functions
Topic A: Lessons 3-4: Factoring by grouping
Factoring quadratics by grouping
Factoring quadratics by grouping
Sal factors 4y^2+4y-15 as (2y-3)(2y+5) by grouping.
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