Which of the following is not an irrational number 5sqrt5, sqrt2, 4sqrt4, 4sqrt16?

1 Answer
Apr 13, 2015

Both sqrt(4) and sqrt(16 can be written as rational values
sqrt(4) = 2
and
sqrt(16) = 4
So both 4sqrt(4) and 4sqrt(16) are rational.

5sqrt(5) and sqrt(2) are both irrational.