Answer:
d = [tex]\frac{7}{2}[/tex]
Step-by-step explanation:
The nth term of an arithmetic sequence is
[tex]a_{n}[/tex] = a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₉ = 16 , then
- 12 + 8d = 16 ( add 12 to both sides )
8d = 28 ( divide both sides by 8 )
d = [tex]\frac{28}{8}[/tex] = [tex]\frac{7}{2}[/tex]
