Elementary Algebra

Similar terms are terms whose literal coefficients (or variables) are exactly the same, including their exponents. Terms like the ones below are similar terms: (i) $2x$ and $-5x$ (ii) $3xy$ and $-5xy$ (iii) $6x^2y$ and $3x^2y$ The given expressions are not similar terms because they have different sets of variables. After all, one expression includes the variable, z, while the other expression does not.