Use the Formula for the General Term of an Arithmetic Sequence
-Find $a _ { 11 }$ when $a _ { 1 } = 21 , d = - 3$.
A) $- 9$
B) $- 12$
C) $- 30$
D) 51

Name: Use the Formula for the General Term of an Arithmetic Sequence -Find $a _ { 11 }$ when $a _ { 1 } = 21 , d = - 3$. A) $- 9$ B) $- 12$ C) $- 30$ D) 51
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Question

Quizplus · Accepted Answer

The formula for the nth term of an arithmetic sequence is $a_n = a_1 + (n - 1)d$. Substituting $a_1 = 21$, $d = -3$, and $n = 11$, we get $a_{11} = 21 + (11 - 1)(-3) = 21 - 30 = -9$.

Use the Formula for the General Term of an Arithmetic a11a _ { 11 }a11​

Use the Formula for the General Term of an Arithmetic $a _ { 11 }$