If a baseball player hits a baseball from 4 feet off the ground with an initial velocity of 64 feet per second, how long will it take the baseball to hit the ground? Use the equation h = –16t2 + 64t + 4.

@hedyeh99

Question

If a baseball player hits a baseball from 4 feet off the ground with an initial velocity of 64 feet per second, how long will it take the baseball to hit the ground? Use the equation h = –16t2 + 64t + 4.

@hedyeh99

tkhunny · Answer

Solve: $–16t^2 + 64t + 4 = 0$ with t > 0

anonymous · Answer

it has to have a radical in it, so how would i set it up?

The answers are: 
2+-√17
        ---
          2

2+-√17
--------
      2

2+-4√17

16+-√17
--------
       2

tkhunny · Answer

Ever hear of the Quadratic Formula?

anonymous · Answer

yess. i'm assuming a would be 16, b would be 64? and so on

tkhunny · Answer

Right, but you can divide everything by 4, first, if you like.

Also, discard the negative value.  The ball can't hit the ground BEFORE it is hit!

anonymous · Answer

So.. would it be the second one? that's what i keep getting.

anonymous · Answer

@bhaskarbabu

anonymous · Answer

??

tkhunny · Answer

It cannot be ANY of the given answers.  That "+/-" has to be gone in order for it to be correct.