Xavier shoots a basketball in which the height, in feet, is modeled by the equation,h(t) = -4t2 + 10 + 18, where t is time, in
seconds. What is the maximum height of the basketball?

Respuesta :

Answer:

The maximum height of the basketball is of 24.25 feet.

Step-by-step explanation:

Vertex of a quadratic function:

Suppose we have a quadratic function in the following format:

[tex]f(x) = ax^{2} + bx + c[/tex]

It's vertex is the point [tex](x_{v}, y_{v})[/tex]

In which

[tex]x_{v} = -\frac{b}{2a}[/tex]

[tex]y_{v} = -\frac{\Delta}{4a}[/tex]

Where

[tex]\Delta = b^2-4ac[/tex]

If a<0, the vertex is a maximum point, that is, the maximum value happens at [tex]x_{v}[/tex], and it's value is [tex]y_{v}[/tex].

Height of the basketball:

Given by the following function:

[tex]h(t) = -4t^2 + 10t + 18[/tex]

Which is a quadratic function with [tex]a = -4, b = 10, c = 18[/tex]

What is the maximum height of the basketball?

y(in this case h) of the vertex. So

[tex]\Delta = b^2-4ac = 10^2 - 4(-4)(18) = 388[/tex]

[tex]y_{v} = -\frac{388}{4(-4)} = 24.25[/tex]

The maximum height of the basketball is of 24.25 feet.