Like terms
Like terms are terms with the same variable part. 3x and 5x are like terms; 3x and 3x² are not.
Like terms combine by adding their coefficients: 3x + 5x = 8x. That is why y + y + y simplifies to 3y.
Like terms are terms with the same variable part. 3x and 5x are like terms; 3x and 3x² are not.
Like terms combine by adding their coefficients: 3x + 5x = 8x. That is why y + y + y simplifies to 3y.