How do I slove this word problem

Question

the diagram shows the path of a model rocket launched from the ground. It reaches a maximum altitude of 384 ft when is it above a location 16ft from the launch site. What quadratic function models hight of the rocket?

Answer 1

Hello, Sarah

Let me try to help you out.  This going to be a parabola concave down. It has a vertex at ( 16, 348).  Remember, when you move horizontally, this is the x value.  When you move up, that is the y value.  

The equation of a parabola using its vertex is 

y= a(x-h)^2 + k, so this parabola will be

y= -a (x- 348)^2+ 16

 

It is negative a because this is a parabola that is concave down or a U upside down.  I hope this helps a little.

 

D.Y. T.

dont forget to rate me :)