Stephanie B. answered • 06/21/19
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The question gives you V0 as 220, so plug that in first.
h=-16t2+220t.
Then it says to find the time (solve for t), when the height is 400 ft. Plug 400 ft in as h and solve for t.
400=-16t2+220t.
To solve this, set the quadratic equal to 0 by subtracting 400 from both sides (0=-16t2+220t-400) and use the quadratic formula!
Stephanie B.
True! That is the rest of the problem, yes. I was merely giving Brittany the start on the path to find the answer, as I would rather give the means and way as apposed to just the answer.
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06/21/19
Terry F.
That's all very accurate but not particularly helpful or insightful. When you do what she suggests, you will find there are two solutions for the arrow on the way up ( approximately 2.2 seconds ) and the arrow on the way down ( approximately 11.6 seconds ) Remember your quadratic formula typically gives you two solutions:; PLUS OR MINUS THE RADICAL06/21/19