After his final exam, a student goes to the top of a building and throws his book into the air. The height h in feet of the book above the ground is given by: h = −16t 2 + 96t + 112. How long is the book in the air

Question

After his final exam, a student goes to the top of a building and throws his book into the air. The height h in feet of the book above the ground is given by: h = −16t 2 + 96t + 112. How long is the book in the air

anonymous · Answer

when it falls to the ground what will be the book's height??

anonymous · Answer

set this sucker = 0 and solve for t

anonymous · Answer

ok let me try it can someone else do it as well

anonymous · Answer

hmm didnt see that - so obvious!

anonymous · Answer

sure. divide by -16 and complete the square

anonymous · Answer

-16t^2 + 96t + 112=0
t^2 - 6t - 7=0
t^2 - 7t + t -7=0
t(t-7) + 1(t-7)=0
t=7 (neclect -1)

anonymous · Answer

that what i got .

anonymous · Answer

ok i got it too thanks, i may be back to check some formulas