The answer is 14. y = 14 hope it helps.
Ok, first you need to combine the like terms, or you can use a different method. It should get easy from there
They are length and width. the only thing is that they do not have volume
ANSWER
Explicit formula:

Recursive

EXPLANATION
The first term of the sequence is

The common difference is


The nth term is given by the formula,



The explicit formula is;

The recursive definition is
