Final answer:
The common difference of the arithmetic sequence -38, -138, -238, -338, -438 is -100, which is the result of subtracting the first term from the second term.
Step-by-step explanation:
The student has provided us with an arithmetic sequence and has asked us to find the common difference. The given sequence is −38, −138, −238, −338, −438. To find the common difference of an arithmetic sequence, we subtract any term from the term that follows it in the sequence.
For instance, if we subtract −38 (the first term) from −138 (the second term), we get:
−138 − (−38) = −138 + 38 = −100
Therefore, the common difference for this arithmetic sequence is −100. This difference remains consistent throughout the sequence, confirming that it is indeed an arithmetic sequence.