Alright so if I do remember my math correctly, this is how it goes:
- y = -x^2 + x + 3
- x = -b/2a
- x = -1/2(-1)
- x = -1/-2, which = (1/2)
Not quite sure if this was correct, but if it was, hope this helps and you're welcome! :)
This is what I got hope u get it right gl

.... Hope this will help....