PP1 (Shorter) Quant Section 1 (Medium) Q4

Question is in the comments.

I set up the (x^2 -1 = 4) equation intuitively without considering if x could be the least number. Could this blind spot hurt me on some questions and how?

One: if the x > 0 condition was not there, you might miss a negative value of x. Second: consider when x^2 < x.

Noted.