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If n is rational, it means that

Therefore when we do n² we can write it as

Remember that the product of two integer numbers is also an integer, therefore we can guarantee that

Then we can confirm that n² is the quotient of two integers and the denominator is not zero, therefore, n² is always rational, it cannot be an irrational number
-9/ 3= -3
-3 + -4 + -2 = -9
the numbers are -2 , -3 , -4