Simplify algebraic expressions

Simplify the algebraic expression
 $z+15-9$  

Simplify the algebraic expression
 $2z+5+3z$  

Simplify the algebraic expression
 $12z+2y+3z-y$  

Simplify the algebraic expression
 $14b\ +12-9b$  

Simplify the algebraic expression
 $b+10-5$  

Simplify the algebraic expression
 $11m+2n+4m-n$  

Simplify the algebraic expression
 $5b+7-3b$  

Simplify the algebraic expression
 $10m+12+5n+3m-3n$  

Simplify the algebraic expression
 $12a+18-6a$  

Simplify the algebraic expression
 $13m-25+m$