How do you simplify #4sqrt(20)-sqrt(45)+7sqrt5#?

1 Answer
Apr 6, 2018

First, you need to properly factor all of your roots. This starts with the #4sqrt(20)# where you must factor out a 2, leaving #8sqrt(5)#. Then on the #sqrt(45)# factor out a 3, leaving #3sqrt(5)#. Now you are left with #8sqrt(5)-3sqrt(5)+7sqrt(5)#. By combining like terms you have #12sqrt(5)#