I was working on some quadratic equations and wondered if I could try and solve an equation without using the formula. Could you tell me if my method is correct? I tried solving it this way to improve my command over the mathematical language and to see if I've understood the concept correctly. What I did was take an equation who's x^2 coefficient was > 1 and convert it into the vertex form to further solve it. 

The way I went about it was: 

[![enter image description here](https://i.stack.imgur.com/E2Dz6.png)](https://i.stack.imgur.com/E2Dz6.png)