Question 1208731: An object is propelled vertically upward with an initial velocity of 20 meters per second. The distance s (in meters) of the object from the ground after t seconds is given by s = -4.9t^2 + 20t.
A. When will the object be 15 meters above the ground?
For part A, I must let s = 15 and solve for t. You say?
B. When will the object strike the ground?
For part. B, I must let s = 0 and solve for t. Correct?
C. When will the object reach a height of 100 meters?
For part C, let s = 100 and solve for t.
Am I correct?
Found 2 solutions by ikleyn, math_tutor2020:
Answer by ikleyn(52798)   (Show Source):
You can put this solution on YOUR website! .
Yes, you must solve it.
Especially for part (C), because when you try to do it,
you will discover other issues, that will require your analysis.
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Answer by math_tutor2020(3817)  (Show Source):
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