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NEED HELP ASAP! 40 POINTS!

NEED HELP ASAP! 40 POINTS!-example-1
User Doolan
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8.2k points

2 Answers

1 vote

Since the functions represent the heights of the rockets, and we are trying to find when the heights are the same, we essentially just want to know where the functions equal each other.


To find this, let's set both functions equal to each other and solve:


-16x^2 + 74x + 9 = -16x^2 + 82x

  • Set up equation


74x + 9 = 82x

  • Add
    16x^2 to both sides of the equation


9 = 8x

  • Subtract
    74x from both sides of the equation


\boxed{x = (9)/(8)}

  • Divide both sides of the equation by 8

Our answer is 9/8 seconds, or approximately 1.13 seconds.

User Marek Szmalc
by
8.1k points
5 votes

Same height when both equations are equal

-16x^2 + 74x + 9 = -16x^2 + 82x

82x - 74x = 9

8x = 9

x = 9/8

x = 1.125

x = 1.13 ---->rounded to nearest hundredths of seconds

answer

1.13 seconds


User Jeremy Grand
by
9.1k points

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