Post a New Question

Math - solving quadratic equations with factoring

posted by .

A person jumps off a 20m high cliff into water below. The height of the person above the ground at time t seconds is given by the equation h=-5t^2+30. How long does it take the person to reach the half way mark to the water?

  • Math - solving quadratic equations with factoring -

    10 = -5t^2 + 30

    5t^2 = 20
    t^2 = 4
    t = 2

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Science

    Ok so I have to use kinematic equations to solve these. But I make like a X and Y chart Ex...X|Vix=2.89 dx=?
  2. Physics

    Ball is thrown horizontally off a cliff with an initial speed of 20m/s. a) how long does it take the ball to hit the ground 20m below. b)how long would it take to hit the ground if it was dropped from the cliff?
  3. math

    i really need help, i have no idea how to answer this question ! A stone is thrown off a cliff. it reaches a maximum height of 30m after 2 seconds, then falls into the water below. it hits the water after 5 seconds a) how high above …
  4. math

    really need help, i have no idea how to answer this question ! A stone is thrown off a cliff. it reaches a maximum height of 30m after 2 seconds, then falls into the water below. it hits the water after 5 seconds a) how high above …
  5. math

    really need help, i have no idea how to answer this question ! A stone is thrown off a cliff. it reaches a maximum height of 30m after 2 seconds, then falls into the water below. it hits the water after 5 seconds a) how high above …
  6. math help please !!!

    i really neeed help, i have no idea how to answer this question ! i tried everything i know! A stone is thrown off a cliff. it reaches a maximum height of 30m after 2 seconds, then falls into the water below. it hits the water after …
  7. math

    The total hang time T in seconds, is given by T(h)=^h/2. Where h is the maximum height. If a person jumps 6 ft off the ground, determine for how many seconds the person is in the air.
  8. Pre Calculus 12

    Modelling with sine/cosine A Ferris wheel has a diameter of 30m. The bottom of the wheel is 1.5m off the ground it takes 3.5min to make one complete revolution. a person gets on ferris wheel at its lowest point at time = 0. write an …
  9. Math

    A person jumps off a 20m high cliff into the water below. The height of the person above the ground at t time seconds is given by the equation h=-5t^2+30. How long does it take the person to reach the half way mark to the water?
  10. Math

    A high school senior vacationing in Jamaica for her senior class trip jumped off a 20 foot cliff into a pool of water. The height of the senior above the water is modeled by the function h(t)=-t^2+t/4+5/4 where h(t) is the height of …

More Similar Questions

Post a New Question