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David is throwing a stone in the air at an angle from the ground with an initial velocity of 30 feet per second. The equation h=-10t2 + 40t +2 gives the height of the stone thrown. Find the maximum height of the stone

User Ofer Zelig
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1 Answer

2 votes

Answer:

42 feet

Explanation:

The vertex of the quadratic function described by the equation is located at ...

t = -(40)/(2(-10)) = 2

The value of height at t=2 is ...

h = -10(2²) +40(2) +2 = -40 +80 +2 = 42 . . . . feet

The maximum height is 42 feet.

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The equation gives the vertical speed at t=0 as 40 ft/sec, which is in contradiction to the number given in the problem statement as the initial velocity. We have used the given equation to answer the question. Since we don't know the throwing direction, we cannot properly adjust the equation to match the description of the scenario.

User Quisquella
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