Final answer:
The equation √x-1 = -4 has no solution since the square root of a real number cannot be negative.
Step-by-step explanation:
The question asks, What is the solution to the equation? √x-1 = -4. Since the square root of a number is always non-negative, the equation cannot hold true with a negative number on the right side (-4 in this case). This is because there is no real number that, when squared, equals a negative number. Therefore, the equation √x-1 = -4 has no solution in the set of real numbers.