Answer:
arithmetic sequence with d = 5
Step-by-step explanation:
The sequence is arithmetic if a common difference d exists between consecutive terms
d = [tex]a_{2}[/tex] - [tex]a_{1}[/tex] = [tex]a_{3}[/tex] - [tex]a_{2}[/tex] = ....
a₂ - a₁ = - 7 - (- 12) = - 7 + 12 = 5
a₃ - a₂ = - 2 - (- 7) = - 2 + 7 = 5
a₄ - a₃ = 3 - (- 2) = 3 + 2 = 5
Since there is a common difference of 5 between consecutive terms of the sequence, it is arithmetic