1. -11x : when you subtract a negative from a negative it makes the number smaller but bigger, meaning -11 is smaller than -10 because you took away one x
2. 7x+25 : PEMDAS first so make sure to distribute the 7. Then add
3. -10xy : distribute the 5 to the -2
4. 11k-1 : distribute the 3, then add like terms together
5. -20y+15 : Distribute in both sets of parenthesis, then add like terms
6. Same as above
7. 5b -8 : Distribute and add like terms