256,076 views
28 votes
28 votes
Graph the function. Be sure to identify Katie's start and end points on the graph.

Graph the function. Be sure to identify Katie's start and end points on the graph-example-1
User Antichris
by
2.8k points

1 Answer

26 votes
26 votes

INFORMATION:

We know that the function that describes Katie's parabolic trajectory is


h(t)=-16t^2+16t+672

And we must graph it, identifying Katie's start and end points

STEP BY STEP EXPLANATION:

Since we have a parabola, we can calculate the vertex to graph it

The formula for the vertex is


x=(-b)/(2a)

In this case, a = -16 and b = 16

Now, replacing in the formula


x=(-16)/(2(-16))=(1)/(2)

Now, we must replace t = 1/2, to find the coordinate of the vertex


\begin{gathered} h((1)/(2))=-16((1)/(2))^2+16\cdot(1)/(2)+672 \\ h((1)/(2))=676 \end{gathered}

Then, the coordinate of the vertex is (1/2, 676)

Now, we can find the x intercepts if we equal the function to 0 and solve for t


\begin{gathered} -16t^2+16t+672=0 \\ -16(t^2-t-42)=0 \\ -16(t-7)(t+6)=0 \\ \text{ Solving for t,} \\ t=7,t=-6 \end{gathered}

Now, knowing the vertex and the x-intercepts we can graph the function

In the graph we take the positive part of the parabola because t (x-axis) represents time and the time must be positive

The end point would be when h(t) = 0

ANSWER:

Graph the function. Be sure to identify Katie's start and end points on the graph-example-1
Graph the function. Be sure to identify Katie's start and end points on the graph-example-2
User Rinuthomaz
by
2.6k points