With the help of variable, find the rule which gives the number of matchsticks needed to make the pattern.
 
1. A pattern of letter \(Z\) as z.png is i.
 
[Note: Use \(y\) as the variable to write the rule]
 
 
2. A pattern of letter \(B\) as b.png is i.
 
[Note: Use \(y\) as the variable to write the rule]