Yes. Factors that complete a factor tree need to be prime. However, it doesn't matter what two factors you select to start a factor tree.
There is no factor tree nor factors of 57 as it is a prime number.
NEVER! A factor tree is strictly division. Factors at the end of a factor tree should all be whole numbers.
it is the factors of 189
In doing the factor tree, you can start with any two factors of the given number. These factors maybe prime or composite. But the resulting factors in the factor tree should always be prime numbers. It means that you have to continue factoring unless you ended up with all prime factors.
39 3,13
A factor tree has factors, not square roots - unless they are integers.
The purpose of a factor tree is to divide a number into prime factors. 1 is not a prime number.
prime factors
All factors of a number
the prime factor of 5
When the bottom branch consists entirely of prime numbers.