Question

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

Answer 1

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)`