Question 1140216


A) What is the height of the ball one second after you release​ it? 

Find 

the value of h in the formula 

{{{h=-16t^2+48t+160}}} when {{{t​ = 1}}}:

 {{{h=-16*1^2+48*1+160}}}

{{{h​ =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^2+48t+160 }}} when {{{h​ = 0}}}.

{{{0=-16t^2+48t+160 }}}.............factor completely

{{{16(t^2-3t-10)=0 }}}

{{{16(t^2+2t-5t-10)=0 }}}

{{{16((t^2+2t)-(5t+10))=0 }}}

{{{16(t(t+2)-5(t+2))=0 }}}

{{{16 (t - 5) (t + 2) = 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