add 3 square root 21 + 7 square root 21

10 square root 21
10 square root 42
square root 52
square root 24 + square root 28

1 answer

The given expression is "3√21 + 7√21".

When we combine the like terms, we get: (3 + 7)√21 = 10√21

So the simplified expression is "10√21".