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), xxx seconds after Amir threw it, is modeled by

h(x)=-(x+1)(x-7)

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

________ seconds

I know I literally just posted one a couple minutes ago but, please help me again T-T

Answer 1

The ball will reach its maximum height 3 seconds after being thrown.

Step-by-step explanation:

To find the time when the ball reaches its maximum height, we need to determine the vertex of the quadratic equation representing the ball's height. The equation h(x)=-(x+1)(x-7) can be rewritten in vertex form as h(x)=-x^2+6x-7. The x-coordinate of the vertex can be found using the formula x = -b/2a, where a, b, and c are the coefficients of the quadratic equation.

In this case, a = -1 and b = 6. Plugging these values into the formula, we get x = -6/-2 = 3. Therefore, the ball reaches its maximum height 3 seconds after being thrown.

Answer 2

3 seconds

Step-by-step explanation:

The given equation describes a parabolic curve with zeros at x=-1 and x=7. The line of symmetry of the curve is halfway between the zeros, at ...

x = (-1 +7)/2 = 6/2 = 3

The maximum of the curve is on the line of symmetry. The ball will reach its maximum height 3 seconds after being thrown.

_____

Additional comment
The maximum height will be 16 meters.