Answer:
84
Step-by-step explanation:
The sequence is:
An=2a(n-1)+4
The first term is:
a1=7
So, lets find out A2.
A2 = 2A(2-1) +4
A2 = 2*A1 + 4
A2 = 2*7 + 4
A2 = 14 + 4 = 18
The third term, A3 is:
A3 = 2A(3-1) +4
A3 = 2*A2 + 4
A3 = 2*18 + 4 = 36+4 = 40
Finally, the fourth term, A4 is:
A4 = 2A(4-1) +4
A4 = 2*A3 + 4
A4 = 2*40 + 4 = 80+4 = 84
The 4th term is 84.
