Question

a ball is shot out of a homemade air cannon. It flies through the air such that its height, as a function of time, is given by: h= -16t^2 + 64t + 10. where h is the height of the ball in feet and t is the time since it was fired in seconds. Max estimates that it takes 4 seconds for the ball to hit the ground and Cole estimates it takes 5 second. Algebraically determine who is closer and support your answer.

Answer 1

Max

Explanation:

the function given that h = -16t³+64t+10

the general function Equation:

h = at²+bt+c

=> t at the highest point is defined by t = -b/2a

= -64/2(-16) = -64/-32 = 2 second

the total times that the ball hits the ground

= 2× 2 seconds = 4 seconds.

so, Max is right

Answer 2

Solution given:

Let h=0=when the ball hit the ground,the height=0.

h= -16t^2 + 64t + 10.

0=16t²-64t-10

8t²-32t-5=0

∆=
`(32±√(32²+4*5*8))/(2*8)=(8±√(74))/(4)`

taking positive

t1=
`(8+√(74))/(4)=4.15seconds`

t2=
`(8-√(74))/(4)(t2<O)(neglected)`

So

t=4.15seconds closer to 4seconds.So

Max is closer.