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HURRY HELP PLS‼️‼️‼️

10. Use the projectile motion formula and solve the quadratic equation.
Melissa drops a tennis ball from the roof of a building that is 256 feet
high. How long does it take the tennis ball to hit the ground?
Original content Copyright by Houghton Mifflin Harcourt. Additions and changes to the original content are the resp

User Shawn Yap
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Answer:

Explanation:

To solve this problem you need the function

h(t) = -16t2 + v0t + h0

where t = time

v0 is the initial velocity, which in our case is 0

h0 = initial height, which in our case is 256

h(t) = 0 since we want to know when the ball will hit the ground.

0 = -16 t2 + 256

And we can solve for t

If we rearrange the terms we see that this is a difference of 2 squares

0 = 256 - 16t2

0 = (16-4t)(16+4t)

Setting each factor = 0

16-4t=0 16+4t=4

t = 4 t = -4

The second solution is discarded as time cannot be negative.

So the ball will hit the ground in 4 seconds.

User Netloh
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