Question 251316
Solve the problem. Round to the nearest tenth, if necessary.
A rock falls from a tower that is 432 feet high. As it is falling, it's height is given by the formula h= 432- 16t^2.
 How many seconds will it take for the rock to hit the ground (h=0)?
:
432- 16t^2 = 0
-16t^2 = -432
Multiply both sides by -1
 16t^2 = 432
 t^2 = {{{432/16}}}
 t^2 = 27
 t = {{{sqrt(27)}}}
 t = 5.2 sec
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Check solution on calc:
Enter -16(5.2^2) + 432 = -.6 ~ 0