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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
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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
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2.6k points