I have never understood these. Help.

Answer:
5 sqrt(5)
Step-by-step explanation:
sqrt(125)
sqrt( 25*5)
We know that sqrt(ab) = sqrt(a) sqrt(b)
sqrt(25) sqrt(5)
5 sqrt(5)
Answer:
5√(5)
Step-by-step explanation:
Notice that 125 is 25×5
If you couldn't do it use the prime factorization.
Prime numbers are 2,3,5.....
125 isn't divisible by 2 and 3 so we'll go with 5.
● 125 ÷ 5 = 25
Againg 25 is divisible by 5
● 25÷5 = 5
5 is divisible by 5
● 5÷5=1
So 125= 5×5×5 = 5^2 × 5
● √(125)= √(5^2×5) = 5√(5)