Examine the function $y = x^2 - 4x + 3$ and determine:
- if the curve has a maximum or minimum point?
- the function's zeroes
- the function's line of symmetry,
- coordinates of the turning point
To answer all your questions, try to complete the square so that the function is written in the form $$y = a(x-b)^2 + c.$$ In this form, it is easy to determine whether the function has a maximum or a minimum (this will depend on the value of $a$), the zeros (this will depend on $a$, $b$, and $c$), the line of symmetry (depends on $b$), and the turning point (again, depends on $b$).