SOLUTION: 1. A projectile that is fired vertically into the air with an initial velocity of 120 ft. per second can be modeled by the equation s = 120t - 16t2. In the equation, s is the dis

Algebra ->  Functions -> SOLUTION: 1. A projectile that is fired vertically into the air with an initial velocity of 120 ft. per second can be modeled by the equation s = 120t - 16t2. In the equation, s is the dis      Log On


   



Question 1172179: 1. A projectile that is fired vertically into the air with an initial velocity of 120 ft. per second can be modeled by the equation s = 120t - 16t2. In the equation, s is the distance in feet of the projectile above the ground after t seconds. Show clear solutions thanksss!

a. How long will it take for a projectile to reach 216 feet?
b. Is it possible for the projectile to reach 900 feet? Justify your answer.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
A projectile that is fired vertically into the air with an initial velocity of 120 ft. per second can be modeled by the equation s = 120t - 16t2. In the equation, s is the distance in feet of the projectile above the ground after t seconds. Show clear solutions thanks
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a. How long will it take for a projectile to reach 216 feet?
s(t) = 120t - 16t^2 ----- use ^ (Shift 6) for exponents.
120t - 16t^2 = 216
Solve for t.
2 values, ascending and descenging
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b. Is it possible for the projectile to reach 900 feet? Justify your answer.
s(t) = 120t - 16t^2
900 = 120t - 16t^2
IFF there's a real number solution, it is possible.
IFF = if and only if
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You can solve for the max height, and see if it's less than 900