The solution of the equation [tex]-x^2+2x+3=x^2-2x+3[/tex] are the x-coordinates of common points on the graphs of the function [tex]y=-x^2+2x+3[/tex] and [tex]y=x^2-2x+3.[/tex]
As you can see from the attached diagram these graphs intersect at points (0,3) and (2,3), then the solutions of the previous equation are x=0 and x=2.
Answer: x=0, x=2.