negative 81 comma 108 comma negative 144 comma 192 comma dot dot dot Which formula can be used to describe the sequence?

The sequence is geometric because each term is multiplied by the same ratio: 108 ÷ (−81) = −4/3, and −144 ÷ 108 = −4/3. A geometric sequence has formula f(x) = first term × ratio^(x − 1). Using first term −81 and ratio −4/3 gives f(x) = −81(−4/3)^(x − 1), which is choice B.

AI-written and checked against the verified answer.