Question

multiple choice,
State whether the following sequence is arithmetic; and if so, state the common difference.
-1, -3, -5, -7, ...
1)2
2)-2
3)not arithmetic
4)-3

Answer 1

Do the differences below all have the same answer ?
(-7)-(-5)=?
(-5)-(-3)=?
(-3)-(-1)=?

Answer 2

i have no idea!

Answer 3

The 4th number minus the third number:
(-7)-(-5) = -7 + 5 = 5 - 7 = -2

The 3rd number minus the second number:
(-5)-(-3) = -5 + 3 = 3-5 = -2

etc.

If you check all the numbers, you will see that the difference between each number in the sequence and the previous number in the sequence is always -2

Answer 4

This means it is an arithmetic sequence, and the common difference is -2.

Answer 5

oh!!!!! thankyou!