Question

which best describes the relationship between the successive terms in the sequence shown?

(9, -1, -11, -21, \dots)

• the common difference is (-10).
• the common difference is (10).
• the common ratio is (-9).
• the common ratio is (9).

Explanation:

Identify the sequence type

$$ a_1 = 9,\ a_2 = -1,\ a_3 = -11,\ a_4 = -21 $$

Calculate successive differences

$$
LATEXBLOCK0
$$

Determine the common difference

$$ d = -10 $$

Answer:

• The common difference is -10. (Correct answer)
• The common difference is 10.
• The common ratio is -9.
• The common ratio is 9.