Question

Katie is finding the standard form of the conic parabola. State her mistake by giving the correct vertex.
Here's a link to the problem: http://i45.tinypic.com/jgo08g.gif

Answer 1

She adds a 9 into one side of the equation but it doesn't add it to the other side, which is in line 2

Answer 2

What would the vertex be? This is a little hard for me to understand(trying to help sis with her hw)

Answer 3

When you add the 9, you need to add 9 to the other side too:
y+9=x^2 + 6x + 9 + 4
y+9=(x+3)^2 +4
y=(x+3)^2 -5