What is the explicit formula for this sequence?

Answer:
C. aₙ = 7 + (n-1)(-4)
Step-by-step explanation:
a₁ =7 a₂ = 7-4 = 3 a₃ = 3 - 4 = 7-4 -4 = 7- 4* ( 3-1) = -1
aₙ = 7 + (n-1)(-4)