The vertex form for a parabola is where(h, k)is the vertex. Your equation looks like this:

Notice the thathmust equal+3because there's a negative sign in the vertex form of the equation. Just remember to change the sign. That's all.

In your second example , you have a positive sign inside parentheses. The only way that can happen is ifhis negative.

Bottom line..when you take that coordinate out of parentheses, change its sign.