Question

Which number is irrational?

A. square root of 5
B. 0.777...
C. 0.454545...
D. 0.3

Answer 1

irrational numbers are number that can't be written in a/b form where a and b are integers and b≠0

if it repeats, it can be written as a fraction

if it terminates, it can also be written as a fraction

if you have a square root that doesn't simplify nicely, we assume it to be irrational

so

A. 0.454545=45/99

B. irrational

C. 7/9

D. 3/10

Answer 2

A

Explanation:

The square root of 5 is irrational because it cannot be expressed as a fraction.

Meanwhile, all 3 other answer choices are not irrational because they can be put into fraction form.