Khan Academy (English - US curriculum)
Math by grade
Illustrative Mathematics
7th grade (Illustrative Mathematics)
Unit 6: Expressions, equations, and inequalities
Lesson 21: Combining like terms (part 2)
Lesson 21: Combining like terms (part 2)
Combining like terms with negative coefficients & distribution
Combining like terms with negative coefficients & distribution
Equivalent expressions: negative numbers & distribution
Equivalent expressions: negative numbers & distribution
