ANSWER
3. 18, 5.5, –7, –19.5, –32, …
and
5. 16, 32, 48, 64, 80
EXPLANATION
An arithmetic sequence has a constant difference.
1. –5, 5, –5, 5, –5, … is not an arithmetic sequence because 5--5≠ -5-5
2. 96, 48, 24, 12, 6 is not an arithmetic sequence because 48-96≠ 24-48
3. 18, 5.5, –7, –19.5, –32, … is an arithmetic sequence because there is a constant difference of
[tex]5.5 - 18 = - 12.5[/tex]
4. –1, –3, –9, –27, –81, … is not an arithmetic sequence because
[tex] - 3 - - 1 = - 9 - - 3[/tex]
5. 16, 32, 48, 64, 80 is also an arithmetic sequence because
[tex]32 - 16 = 48 - 32[/tex]
