# What is the vertex form of y=x^2 - 8x + 16 ?

It is $y = {\left(x - 4\right)}^{2}$

#### Explanation:

The vertex form of a parabola's equation is generally expressed as :

$y = a \cdot {\left(x - h\right)}^{2} + k$

Hence the given parabola can be written as follows

$y = {\left(x - 4\right)}^{2}$

so it is $a = 1$ , $h = 4$, $k = 0$

So the vertex is $\left(h = 4 , k = 0\right)$

graph{(x-4)^2 [-1.72, 12.33, -0.69, 6.333]}