Question

How do you simplify `-4sqrt6+7sqrt54`?

Answer 1

I found: `17sqrt(6)`

Explanation:

You can write `54=6*9` and so:
`-4sqrt(6)+7sqrt(6*9)=`
`=-4sqrt(6)+7sqrt(6)sqrt(9)=`
but `sqrt(9)=3`
so:
`=-4sqrt(6)+7*3sqrt(6)=`
`=-4sqrt(6)+21sqrt(6)=17sqrt(6)`