Math

An object is propelled vertically upward from the top of a 144-foot building. The quadratic function s(t)= -16t2+192+144 models the ball's height above the ground, in feet, s(t) seconds after it was thrown. How many seconds does it take until the object finally hits the ground? Round to the nearest tenth of a second if necessary.
Answer

0.7 seconds

  1. 👍
  2. 👎
  3. 👁
  1. when it hits the ground, s(t) = 0
    -16t^2 + 192t + 144 = 0
    t^2 - 12t - 9 = 0
    I will complete the square rather than use the quadratic formula
    t^2 - 12t + 36 = 9 + 36
    (t-6)^2 = 45
    t-6 = ±√45
    t = 6 ± √45
    = appr -.7 or 12.7

    since t > 0, it will hit the ground 12.7 after it was tossed.

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. Algebra

    THe function h(t)=-16t^2+v0t+h0 describes the height in feet above the ground h(t) of an object thrown vertically from a height of h0 feet, with an initial velocity of v0 feet per second, if there is no air friction and t is the

  2. college algebra

    A contractor leans a 23-foot ladder against a building. The distance from the ground to the top of the ladder is 7 feet more than the distance from the building to the base of the ladder. How far up the building is the ladder to

  3. Calculus

    A contractor leans a 23-foot ladder against a building. The distance from the ground to the top of the ladder is 9 feet more than the distance from the building to the base of the ladder. How far up the building is the ladder to

  4. Algebra

    If an object is dropped from a height of 144 ft, the function h(t) = –16t² + 144 gives the height of the object after t seconds. When will the object hit the ground? • 1.5 s • 3 s • 6 s • 9 s

  1. Algebra

    THe function h(t)=-16t^2+v0t+h0 describes the height in feet above the ground h(t) of an object thrown vertically from a height of h0 feet, with an initial velocity of v0 feet per second, if there is no air friction and t is the

  2. Physics

    Q.1 A ball is thrown 233 m upward and then falls back to earth. Neglecting air resistance, how long will it be in the air? The acceleration of gravity is 9.8 m/s2 . Answer in units of s. Q.II An object is thrown downward with an

  3. Math

    An object is projected vertically upward from the top of a building with an initial velocity of 144 ft/sec. Its distance s(t) in feet above the ground after t seconds is given by the function s(t) = −16t2 + 144t + 120. A) Find

  4. Physics

    Please Help. A 5 kg object is propelled from rest at time t=0 by a net force F that always acts in the same direction. The magnitude of F in newtons is given as a function of t in seconds by F= 0.5t. What is the speed of the

  1. Math

    An object is thrown from the top of an 80 foot building with an initial velocity of 64 feet per second. The height (h) of the object after (t) seconds is given by the quadratic equation h=-16t+64t+80 .When will the object hit the

  2. math

    an object is thrown upward from the top of a 80-foot building with a initial velocity of 65 feet per second. The height h of the object after t seconds is given by the equation h=-16t2+64t+80. when will the object hit the ground

  3. Calc

    If a ball is thrown vertically upward from the roof of 48 foot building with a velocity of 32 ft/sec, its height after t seconds is s(t)=48+32t–16t2. What is the maximum height the ball reaches?

  4. Math

    A bucket begins weighing 15 pounds, including the sand it holds. The bucket is to be lifted to the top of a 50 foot tall building by a rope of negligible weight. However, the bucket has a hole in it, and leaks 0.1 pounds of sand

You can view more similar questions or ask a new question.