Answer:
The expression for the nth term is Tn = 8n -7
Step-by-step explanation:
Here, we are to find an expression for the nth term of the sequence.
Mathematically, the nth term of an arithmetic sequence can be expressed as;
Tn = a + (n-1)d
for T2, the equation is
a + d = 9
for T4, the equation is
a + 3d = 25
we can substitute the equation of T2 into T4 but we first need to rewrite T4
a + d + 2d = 25
9 + 2d = 25
2d = 25 -9
2d = 16
d = 16/2
d = 8
now since a + d = 9
a = 9-d
a = 9-8
a = 1
So the expression for the nth term would be;
1 + (n-1)8
1 + 8n - 8
= 8n -8+1
= 8n -7
