SOLUTION: A punter kicks a football from 0.8 meters above the ground with an initial velocity of 21 meters per second. The height of the football is modeled by the equation h(t)=−4.9t2+21

Click here to see ALL problems on Linear-systems

Question 1167490: A punter kicks a football from 0.8 meters above the ground with an initial velocity of 21 meters per second. The height of the football is modeled by the equation h(t)=−4.9t2+21t+0.8 where h(t) represents the height of the football in meters and t represents time in seconds.
How many seconds does it take for the receiver to catch the football if he catches it at a height of 1.2 meters?
Answer by ikleyn(52788)   (Show Source):
You can put this solution on YOUR website!
.

To answer your question, solve an equation −4.9*t^2 + 21t + 0.8 = 1.2.

----------------------

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, guide, tutorials, templates 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.