Which of these is an irrational number?

A.. Sq root of 14
B. -sq root of 9
C. -sq root of 34
D. Sq root of 72

Sorry meant rational number?

since 9 is a perfect square, √9 = 3 is rational

To determine which of these options is an irrational number, we need to understand what an irrational number is. An irrational number is a number that cannot be written as a fraction or a ratio of two integers. It is a number with an infinite and non-repeating decimal representation.

To identify an irrational number among the given options, we can check if the square root of the number is rational or irrational.

A. Square root of 14: To determine if it is rational or irrational, we can try to simplify the square root. However, the square root of 14 cannot be simplified to a whole number, fraction, or decimal. Therefore, the square root of 14 is an **irrational number**.

B. -Square root of 9: The square root of 9 is 3, and since there is a negative sign in front, the value of -square root of 9 is -3. -3 can be written as a ratio of two integers (-3/1). Therefore, the -square root of 9 is a **rational number**.

C. -Square root of 34: Similar to option B, we can evaluate the square root of 34. However, the square root of 34 is an irrational number, as it cannot be simplified to an exact whole number, fraction, or decimal. Therefore, the -square root of 34 is an **irrational number**.

D. Square root of 72: We can simplify the square root of 72 by factoring it. The square root of 72 can be written as the square root of 36 times the square root of 2, which simplifies to 6 times the square root of 2. 6 is a rational number, and we have the square root of 2, which is an irrational number. Therefore, the square root of 72 is an **irrational number**.

In summary, among the given options, **options A, C, and D** are irrational numbers.