My friend would be correct and wrong at the same time. They are correct when they say 3x3 equals 9. However, due to them needing to find the square root of a negative, then the imaginary numbers need to be found as well. My friend needs to find the of square root 9, the real number first, and then the imaginary number, which is represented as i for the square root of -1. So the square root of 9 is 3 and then the imaginary number is I. So the square root of -9 is +/- 3i