algebra
posted by ciara .
simplify: 6sqrt7sqrt7
A. 6 sqrt7
B. 5 sqrt 7
C. 5
D. 6
Simplify: 2sqrt12+ sqrt3
A.5sqrt3
B. 3sqrt3
C. 2sqrt15
D. 3sqrt15
Need help on these please

1) B .. Because since they're both sqrt7 base, you can just subtract them.
2) A .. You have to simplify sqrt12 to sqrt4 times sqrt3, so you will get 2(2)(sqrt3) + sqrt3 .. which will turn into 4sqrt3 + sqrt3. Since they're the same base again, it will be 5sqrt3. 
thank you for your help :)