# How do you find the axis of symmetry, graph and find the maximum or minimum value of the function y = x^2 - 4x + 4?

Mar 3, 2016

Min (2, 0)

#### Explanation:

x-coordinate of vertex, or axis of symmetry:
$x = - \frac{b}{2 a} = \frac{4}{2} = 2$.
y-coordinate of vertex:
y(2) = 4 - 8 + 4 = 0.
Since a > 0, the parabola opens upward, there is Min at vertex.
Min (2, 0)
graph{x^2 - 4x + 4 [-10, 10, -5, 5]}