Prime factorization is shows you the only way a number can be factored.
Here are some examples:
6 = 2 x 3
(2 and 3 are prime numbers) If you need to, search up a prime chart of numbers. Also prime numbers is technically how small you can get a number.
Here are some more examples:
12 = 2 x 2 x 3
45 = 5 x 3 x 3
now that you see what it looks like, you may be wondering how did factor those out? Well first find a divisible number. lets use this example;
Factor out 42.
first think of your times table, what two numbers get you to 42, I know that 6 times 7 does so now write it out:
42 = 6 x 7
Is this equation done?
No it is not, 6 can still be factored.
What two numbers get you the product of 6?
they are 3 and 2.
Now the final factored out equation looks like this:
42 = 3 x 2 x 7
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I hope this helps!