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4 votes
4 votes
Can you tell me if my answer is correct

User Venu Duggireddy
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1 Answer

8 votes
8 votes

Answer:

(a)Vertex

(c)3 seconds

Step-by-step explanation:

Part A

The maximum point on a parabola is called the Vertex.

Part C

To find out how much the plain was in the air, find the values of t at which the height, h=0.

Next, subtract the second value of t from the first value.


h=-16t^2+32t+48

First, set h=0:


\begin{gathered} h=-16t^2+32t+48=0 \\ -16t^2+32t+48=0 \end{gathered}

Factorize:


\begin{gathered} -16(t^2-2t-3)=0 \\ t^2-2t-3=0 \\ t^2-3t+t-3=0 \\ t(t-3)+1(t-3)=0 \\ (t+1)(t-3)=0 \\ t+1=0\text{ or }t-3=0 \\ t=-1\text{ or }t=3 \end{gathered}

Therefore, the plane hits the ground after 3 seconds.

User Rafaelzlisboa
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2.7k points