Answer:
B
Step-by-step explanation:
given a quadratic function in standard form
y = ax² + bx + c ( a ≠ 0 ) , then the x- coordinate of the vertex is
x = - [tex]\frac{b}{2a}[/tex]
y = x² - 4x + 3 ← is in standard form
with a = 1, b = - 4 , then
x = - [tex]\frac{-4}{2}[/tex] = 2
substitute into the equation for corresponding y- coordinate
y = 2² - 4(2) + 3 = 4 - 8 + 3 = - 1
vertex = (2, - 1 )
