Question

What is the `3sqrt125` minus `2sqrt80` plus `sqrt405`?

Answer 1

`16sqrt5`

Explanation:

`3sqrt125-2sqrt80+sqrt405`

`3sqrt(25*5)-2sqrt(16*5)+sqrt(81*5)`

`3*5sqrt5-2*4sqrt5+9sqrt5`

`15sqrt5-8sqrt5+9sqrt5`

`7sqrt5+9sqrt5`

`16sqrt5`