SOLUTION: If you throw a ball straight up from a rooftop 160 feet high with an initial speed of 48 feet per​ second, then the formula h=-16t^2+48t+160 describes the​ ball's height h feet

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Question 1140216: If you throw a ball straight up from a rooftop 160 feet high with an initial speed of 48 feet per​ second, then the formula h=-16t^2+48t+160 describes the​ ball's height h feet above the​ ground, t seconds after you released it. The ball misses the rooftop and eventually strikes the ground.

A) What is the height of the ball one second after you release​ it?
Solution​:Find
the value of h in the formula h=−16t^2+48t+160 when t​ = 1.
h​ =_____feet
the answer i got was 196
​b) How long will it take the ball th hit the​ ground?
Solution​:Find the value of t in the formula h=−16t^2+48t+160
when h​ = 0.
It will take _____ seconds for the ball th hit the ground.
the answer i got was 5
Found 3 solutions by MathLover1, ikleyn, MathTherapy:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

A) What is the height of the ball one second after you release​ it?
Find
the value of h in the formula
h=-16t%5E2%2B48t%2B160 when t%E2%80%8B+=+1:
h=-16%2A1%5E2%2B48%2A1%2B160
h%E2%80%8B+=192 feet is correct answer
the answer i got was 196=>incorrect

​b) How long will it take the ball to hit the​ ground?
Solution​:
Find the value of t in the formula h=-16t%5E2%2B48t%2B160+ when h%E2%80%8B+=+0.
0=-16t%5E2%2B48t%2B160+.............factor completely
16%28t%5E2-3t-10%29=0+
16%28t%5E2%2B2t-5t-10%29=0+
16%28%28t%5E2%2B2t%29-%285t%2B10%29%29=0+
16%28t%28t%2B2%29-5%28t%2B2%29%29=0+
16+%28t+-+5%29+%28t+%2B+2%29+=+0
=> t=5 or t=-2-> disregard negative solution for time

It will take __5___ seconds for the ball th hit the ground.
the answer i got was 5=> correct

Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.

In this site,  there is a bunch of lessons 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.


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

If you throw a ball straight up from a rooftop 160 feet high with an initial speed of 48 feet per​ second, then the formula h=-16t^2+48t+160 describes the​ ball's height h feet above the​ ground, t seconds after you released it. The ball misses the rooftop and eventually strikes the ground.

A) What is the height of the ball one second after you release​ it?
Solution​:Find
the value of h in the formula h=−16t^2+48t+160 when t​ = 1.
h​ =_____feet
the answer i got was 196
​b) How long will it take the ball th hit the​ ground?
Solution​:Find the value of t in the formula h=−16t^2+48t+160
when h​ = 0.
It will take _____ seconds for the ball th hit the ground.
the answer i got was 5 
196 in NOT CORRECT, but 5 is!