Question

the first three terms of an arithmetic sequence are as follows.
-11, -16, -21
find the next two terms of this sequence.
-11, -16, -21, □, □

Explanation:

Step1: Find the common difference

To find the common difference \( d \) in an arithmetic sequence, we subtract consecutive terms. Let's take the first two terms: \( -16 - (-11) = -16 + 11 = -5 \). Let's check with the next pair: \( -21 - (-16) = -21 + 16 = -5 \). So the common difference \( d = -5 \).

Step2: Find the fourth term

To find the fourth term, we add the common difference to the third term. The third term is \( -21 \), so the fourth term is \( -21 + (-5) = -21 - 5 = -26 \).

Step3: Find the fifth term

To find the fifth term, we add the common difference to the fourth term. The fourth term is \( -26 \), so the fifth term is \( -26 + (-5) = -26 - 5 = -31 \).

Answer:

-26, -31