In the lessons for Vertex Form here:

- https://www.khanacademy.org/math/algebra/x2f8bb11595b61c86:quadratic-functions-equations/x2f8bb11595b61c86:vertex-form/v/vertex-form-intro

No explanation is ever given for how to get an equation INTO "vertex form" (usually by completing the square).  The comments show people endlessly having this question, so it's not sufficient for it to be addressed in the comments... it needs to be in the course main content. 

At 25 seconds into the intro (https://youtu.be/_QqhuLixNEk?t=25), Sal says, "...we're not gonna focus on how do you get from one of these other forms to a vertex form in this video, we'll do that in future videos..."

But that never happens.

This course needs a video covering how to do that.

On youtube I found an OLD video which used to explain it at the 3:13 mark:

- https://youtu.be/4Bc5-HRop5Y?t=193

The course also seems to be lacking discussion this topic in any Text/Summary document page.

Please add the missing information to the main course content.