I really need help simplifying these problems?

Question

how do you simplify

1. 3√45

2. √75

3. 5√a

____

25√a

4. (-6√6)(2√2)

5. 3√3-√2+6√12+√18

6. 2x^2=100

Answer 1

(1)  3√(5 x 3^2)=9√5

(2) √(3 x 5^2) = 5√3

(3) 1/5

(4) [-6√(2x3)][2√2]=-3√3

(5) 6√12=6√(3x2^2)=12√3

√18=√(2x3^2)=3√2

3√3-√2+6√12+√18=3√3-√2+12√3+3√2=15√3+2...

(6)  x^2=50

x=+/-√50

x=+/-√(2x5^2)

x=+/-5√2