y=√x−2 is graphed by shifting the graph of y=√x down two. y=√x is basically half of a sideways parabola opening to the right for positive y-values. y=√x implies y=+√x, where y equals the positive square root of x, so inputting a value such as 9 for x yields 3 (as opposed to y=±√x which, for 9, yields 3 and -3). Additionally, x cannot be a negative value, so the graph for y=√x starts at the origin (y=√0=0) and curves up and to the right in the first quadrant. y=√x−2 is a transformation of y=√x two units down (as y=x−2 is a transformation of y=x two units down). Thus, the graph of y=√x−2 is:
graph{x^(1/2)-2 [-10, 10, -5, 5]}