# What is the vertex form of y=-4x^2+4x-1 ?

Apr 29, 2018

$y = - 4 {\left(x + \frac{1}{2}\right)}^{2}$

#### Explanation:

Take $- 4$ as a common factor

$y = - 4 \left(\textcolor{g r e e n}{{x}^{2} - x} + \frac{1}{4}\right)$

By completing the Square to the elements in green

$y = - 4 \left(\textcolor{g r e e n}{{\left(x - \frac{1}{2}\right)}^{2} - \frac{1}{4}} + \frac{1}{4}\right)$

$y = - 4 {\left(x + \frac{1}{2}\right)}^{2}$

The Function represents a parabola with the vertex $\left(- \frac{1}{2} , 0\right)$ and opened downwards