Which of these numbers is irrational?
a. sq rt 16
b. sq rt 2
c. sq rt 9
d. sq rt 49

Sqrt16=4
sqrt2=irrational (meaning nevereneding and never repeating)
sqrt9=3
sqrt49=7

answer is B

If you do the square root of 16, you get 4 (4*4=16), so this is rational
If you do the square root of 9, you get 3 (3*3=9), so this is rational
If you do the square root of 49, you get 7 (7*7=49), so this is rational
If you do the square root of 2, you get 1.4142, so this is irrational, since it keeps on repeating
So your answer is B. sq rt 2

Hope this helps!