Answer:
True
Step-by-step explanation:
For the sequence to be arithmetic there must be a common difference d between consecutive terms.
a₂ - a₁ = - 6 - 3 = - 9
a₃ - a₂ = - 15 - (- 6) = - 15 + 6 = - 9
a₄ - a₃ = - 24 - (- 15) = - 24 + 15 = - 9
There is a common diffence between consecutive terms, thus the sequence is arithmetic.
