How do i know if a sequence is arithmetic

if difference of any two cosecutive terms is equal to difference of any other two consecutive terms, then the the given sequence is arithmetic

for example: 2,5,8,11,

5-2 is 3 and 8-5 is also 3.

this was already solved by me with a different person. if you look it up in the search bar at the top of the page, you will get the answer.

step-by-step explanation:

no

step-by-step explanation:

2-7=-5

7-2=5

when you combing like terms for ech expression, 5 and -5. these numbers are not equal to each other.