What is the ninth term of the arithmetic sequence defined by the rule below?
A(n) = -15 + 2(n – 1).
A. 1
B. -1
C. 31
D. -31
To find the ninth term of an arithmetic sequence defined by the rule A(n) = -15 + 2(n – 1), we need to substitute n = 9 into the rule and evaluate it.
A(9) = -15 + 2(9 - 1)
= -15 + 2(8)
= -15 + 16
= 1
Therefore, the ninth term of the arithmetic sequence is 1.
The correct answer is A. 1.
To find the ninth term of the arithmetic sequence defined by the rule A(n) = -15 + 2(n – 1), we can substitute the value of n as 9 into the formula.
A(9) = -15 + 2(9 – 1)
First, we simplify the expression inside the parentheses.
A(9) = -15 + 2(8)
Then, we perform the multiplication.
A(9) = -15 + 16
Finally, we add the two terms.
A(9) = 1
Therefore, the ninth term of the arithmetic sequence is 1.
The correct answer is A.
just use n=9:
A(9) = -15 + 2(9-1)