What are the prime factors of 45?

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Answer 1 · 2018-03-07T11:10:43

$45=3xx3xx5$

When doing prime factors, I like to start with a quick math fact I know (if I know one) and start there:

$45=9xx5$

5 is prime but 9 is not:

$45=3xx3xx5$

3 and 5 are both prime and so we're done

Answer 2 · 2018-03-07T11:14:55

5,3.

Prime numbers from 0 - 10 are: 2,3,5,7.
Lets divide 45 in the short division method using prime numbers only.

$45/5 ->9/3 ->3/3 ->1$

therefore factors of 45 are:

$5*3*3$