# How do you write the quadratic equation given a=-2 and the vertex (-5, 0)?

Nov 1, 2014

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

where $\left(h , k\right)$ is the vertex.

Since $a = - 2$ and $\left(h , k\right) = \left(- 5 , 0\right)$, we have

$y = - 2 {\left[x - \left(- 5\right)\right]}^{2} + 0 = - 2 {\left(x + 5\right)}^{2}$.

I hope that this was helpful.