Algebra 1

Published by Prentice Hall
ISBN 10: 0133500403
ISBN 13: 978-0-13350-040-0

Skills Handbook - Prime Numbers and Composite Numbers - Exercises - Page 786: 20



Work Step by Step

The first step is to write 20 at the top of your factor tree. The next question is what 2 numbers multiply together to get 20. For this example, I used 10 and 2, but it can be solved with the same method using 4 and 5. So, 10 and 2 are written under the 20 as 2 different "branches." For each new number "branching" out from the previous number, you must determine if it is prime. 2 is prime because nothing multiplies to 2 but itself. Circle the number 2 to show its separation from the rest of the factor tree. 10, however, is not prime because 5 and 2 are another set of factors for 10 besides 10 itself. Now, 5 and 2 are both prime, so circle each number separately . Looking at all 3 circled numbers,$2\times2\times5$ would be the prime factorization for 20.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.