Find the indicated term of the sequence.
-The ninth term of the arithmetic sequence $- 14 \sqrt { 3 } , - 9 \sqrt { 3 } , - 4 \sqrt { 3 } , \ldots$
A) $26 \sqrt { 3 }$
B) $- 59 \sqrt { 3 }$
C) $31 \sqrt { 3 }$
D) $- 54 \sqrt { 3 }$

Question

Quizplus · Accepted Answer

The common difference $d$ is $5\sqrt{3}$. The $n$-th term is given by $a_n = a_1 + (n-1)d$. For the ninth term, $a_9 = -14\sqrt{3} + 8(5\sqrt{3}) = 26\sqrt{3}$.

Find the Indicated Term of the Sequence −143,−93,−43,…- 14 \sqrt { 3 } , - 9 \sqrt { 3 } , - 4 \sqrt { 3 } , \ldots−143​,−93​,−43​,…

Find the Indicated Term of the Sequence $- 14 \sqrt { 3 } , - 9 \sqrt { 3 } , - 4 \sqrt { 3 } , \ldots$