SOLUTION: 1.An arrow is shot upward with an initial velocity of 80 feet per second. The height of the arrow, h(t), in terms of the time since the arrow was released t, is h(t)= 80t - 16t².

Algebra ->  Test -> SOLUTION: 1.An arrow is shot upward with an initial velocity of 80 feet per second. The height of the arrow, h(t), in terms of the time since the arrow was released t, is h(t)= 80t - 16t².       Log On


   

Question 1188660: 1.An arrow is shot upward with an initial velocity of 80 feet per second. The height of the arrow, h(t), in terms of the time since the arrow was released t, is h(t)= 80t - 16t². How long after the arrow is released does it reach its maximum height? What is the maximum height?
Found 2 solutions by Shin123, MathTherapy:
Answer by Shin123(626) About Me  (Show Source):
You can put this solution on YOUR website!
Factoring, we get h%28t%29=-16%28t%5E2-5t%29.
Completing the square, we get .
Therefore, the vertex is (2.5,100). Since the vertex is the parabola's highest point when the x2 coefficient is negative, it takes highlight%282.5%29 seconds for the arrow to reach its maximum height, and the maximum height is highlight%28100%29 feet.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

1.An arrow is shot upward with an initial velocity of 80 feet per second. The height of the arrow, h(t), in terms of the time since the arrow was released t, is h(t)= 80t - 16t². How long after the arrow is released does it reach its maximum height? What is the maximum height? 
Unless requested to do so, you don't need to complete the square to get your answers.

Time that it takes for the arrow - after being released - to reach its maximum height: 

Substitute that value for x in the given equation to get the maximum height.

That's IT!!