SOLUTION: A rock is thrown upward from the height of 5 ft with an initial velocity of 48 ft per second. The height h(in feet) of the rock at time t seconds is h(t)=-16t^2+48t+5. When will th

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: A rock is thrown upward from the height of 5 ft with an initial velocity of 48 ft per second. The height h(in feet) of the rock at time t seconds is h(t)=-16t^2+48t+5. When will th      Log On


   



Question 1169487: A rock is thrown upward from the height of 5 ft with an initial velocity of 48 ft per second. The height h(in feet) of the rock at time t seconds is h(t)=-16t^2+48t+5. When will the ball reach a height of 8 ft?
Answer by ikleyn(52858) About Me  (Show Source):
You can put this solution on YOUR website!
.

To find this time moment, solve the equation

    -16t^2 + 48t + 5 = 8.

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In this site,  there is a bunch of lessons on a projectile thrown/shot/launched vertically up
    - Introductory lesson on a projectile thrown-shot-launched vertically up
    - Problem on a projectile moving vertically up and down
    - Problem on an arrow shot vertically upward
    - Problem on a ball thrown vertically up from the top of a tower
    - Problem on a toy rocket launched vertically up from a tall platform

Consider these lessons as your textbook,  handbook,  tutorials and  (free of charge)  home teacher.
Read them attentively and learn how to solve this type of problems once and for all.

Also,  you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this textbook under the topic "Projectiles launched/thrown and moving vertically up and dawn".


Save the link to this online textbook together with its description

Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson

to your archive and use it when it is needed.