Amir stands on a balcony and throws a ball to his dog who is at ground level. The ball's height, in meters above the ground, after t seconds that Amir has thrown the ball is given by:

H (t) = - (t-2) ^2+9

Time t = 2 seconds

It will reach the maximum height after 2 seconds

Completed question;

Amir stands on a balcony and throws a ball to his dog who is at ground level. The ball's height, in meters above the ground, after t seconds that Amir has thrown the ball is given by:

H (t) = - (t-2) ^2+9

many seconds after being thrown will the ball reach its maximum height?

Step-by-step explanation:

The equation of the height!

h (t) = - (t-2) ^2 + 9 = - (t^2 - 4t + 4) + 9

h (t) = - t^2 + 4t - 4+9

h (t) = - t^2 + 4t + 5

The maximum height is at dh/dt = 0

dh/dt = - 2t + 4 = 0

2t = 4

t = 4/2 = 2

Time t = 2 seconds

It will reach the maximum height after 2 seconds