Answer:
The formula is 10 - 3n
Explanation:
For an nth term in an arithmetic sequence
U( n ) = a + ( n - 1)d
Where n is the number of terms
a is the first term
d is the common difference
From the sequence above
a = 7
d = 4 - 7 = - 3
The formula for an nth term is
U(n) = 7 + (n - 1)-3
= 7 - 3n + 3
The final answer is
= 10 - 3n
Hope this helps you.