What is - 2√20-√125 in simplest radical form

√20 the prime factors are 2, 2, 5 so

-2 * √4 * √5

-2*2*√5

-4√5 is the first part,

now for √125, use prime factorization,

all prime factors that make up 125 is

5, 5, 5 so √125 can be separated to √25√5 and √25 = 5 so the second part is 5√5.

now - 4√5 - 5√5 = - 9√5.

therefore answer is - 9√5