Combine like terms. 9 + 3x – 9x + 16 a. 18x + 3x + 16 b. 19x c. 25 – 6x d. 3x + 16
9 + 3x - 9x + 16 Like terms are terms that have the same variable and powers. 9 and 16 are like terms. They don't have any other variables and can easily be solved. 9 + 16 = 25 3x and -9x are like term. They both have the same variable and powers, x. The coefficients, 3 an d-9, don't have to match as long as the variable and powers are the same. 3x - 9x = -6x 9 + 3x - 9x + 16 ⇒ 25 - 6x Choice C.