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PLEASE HELP

Two identical rubber balls are dropped from different heights. Ball 1 is dropped from
a height of 131 feet, and ball 2 is dropped from a height of 272 feet. Use the
function f(t) = -16t2 + h to determine the current height, f(t), of a ball dropped from a
height h, over given time t.
When does ball 2 reach the ground? Round to the nearest hundredth.

User Claudiu
by
6.3k points

1 Answer

6 votes

9514 1404 393

Answer:

4.12 seconds

Explanation:

Use the given initial height for Ball 2 to fill in that value in the function.

f(t) = -16t² +272

You want to find t when f(t) = 0.

0 = -16t² +272

0 = -t² +17 . . . . . . . divide by 16

t² = 17 . . . . . . . . . add t²

t = √17 ≈ 4.123 . . . . take the positive square root

Ball 2 reaches the ground after 4.12 seconds.

User Consuelo
by
6.4k points