The value of x = 0 which is none
He maybe accidently added both of thm .
But if we difference we get 7.
Because - and - =+
So
-11+4=7.
Answer:

Step-by-step explanation:
Given that,
An airthmetic sequence,
261,256,251
We need to find the 50th term.
We have,
first term, a = 261
common difference = 256-261 = -5
The nth term of the AP is given by :

So, the 50th term of the sequence is 16.