Education Quality And Accountability Office (EQAO) Grade 9 Practice Exam

Like terms are terms that share the same variable part—exactly the same variable raised to the same power. The coefficients in front of that shared variable part can be different, and that difference is what you use when you combine like terms. So, terms like 3x and -5x are like terms because they both have the same variable part, x, with the same exponent. Their coefficients can differ, and you would add or subtract those coefficients when simplifying, giving -2x in this case. Terms that have different variable parts, like 3x and 4x^2, are not like terms, because the variable part isn’t the same. Constants are terms with no variable at all; two constants are like terms with each other, since they have the same (empty) variable part. The description that best captures this is that like terms have the same variable part, and their coefficients may differ.