Answer :
Answer:
Step-by-step explanation:
a₁₂ = a₅ + (12-5)d
72 = 23 + 7d
d = 7
a₃ = a₅ + (3-5)d = 23 - 2⋅7 = 9
a₂ = a₃ - d = 9-7 = 2
a₁ = a₂ - d = 2 -7 = -5
Answer:
Step-by-step explanation:
a₁₂ = a₅ + (12-5)d
72 = 23 + 7d
d = 7
a₃ = a₅ + (3-5)d = 23 - 2⋅7 = 9
a₂ = a₃ - d = 9-7 = 2
a₁ = a₂ - d = 2 -7 = -5