# How do you find the vertex of y = x^2-8x+7?

Jan 25, 2016

$V \left(4 , - 9\right)$

#### Explanation:

Factor

$y = {x}^{2} - 8 x + 7$.

That's

$y = {\left(x - 4\right)}^{2} - 9$.

Then, transpose $- 9$ to the other side of the equation, that would be

$y + 9 = {\left(x - 4\right)}^{2}$.

Remember: $x$ is for h and $y$ is for k.

Vertex will be $V \left(4 , - 9\right)$.