Is the square root of any number an irrational number?

no square root of 9 is 3 which is rational

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to be more specific: an irrational number is a number that cannot be expressed as a fraction. Pi, for example, is one of these numbers. If a number is not a perfect square (4, 16, 9, 144, 225, etc.), then it's square root is likely to be an irrational number. For example, the square root of 2 (1.41421356...) is an irrational number because it cannot accurately be expressed as a fraction.