Johnny kicks a ball into the air. Assume the path of the ball can be modeled with a quadratic function. The ball reaches a height of 10 feet and lands on the ground 3 seconds later. Draw and label a graph that models the path of the ball. Write an equation that models the path of Johnny’s ball.

Respuesta :

An equation that models the path of Johnny’s ball is [tex]y = -\frac{40}9(x - 1.5)^2 + 10[/tex]

The maximum height is given as:

[tex]h_{max}= 10ft[/tex]

And the time spent is:

[tex]t = 3s[/tex]

So, the vertex of the ball would be:

[tex]Vertex = (t/2,h_{max})[/tex]

This gives

[tex]Vertex = (3/2,10)[/tex]

[tex]Vertex = (1.5,10)[/tex]

Rewrite properly as:

[tex](h,k) = (1.5,10)[/tex]

The ball is on the floor after 3 seconds.

So, another point on the graph is:

[tex](x,y) = (3,0)[/tex]

A quadratic equation is represented as:

[tex]y=a(x - h)^2 + k[/tex]

Substitute [tex](x,y) = (3,0)[/tex] and [tex](h,k) = (1.5,10)[/tex] in [tex]y=a(x - h)^2 + k[/tex]

[tex]0=a(3 - 1.5)^2 + 10[/tex]

[tex]0=a(1.5)^2 + 10[/tex]

Evaluate the exponent

[tex]0=2.25a + 10[/tex]

Subtract 10 from both sides

[tex]2.25a =- 10[/tex]

Divide both sides by 2.25

[tex]a = -\frac{10}{2.25}[/tex]

Multiply by 4/4

[tex]a = -\frac{40}{9}[/tex]

Substitute [tex]a = -\frac{40}{9}[/tex] and [tex](h,k) = (1.5,10)[/tex] in [tex]y=a(x - h)^2 + k[/tex]

[tex]y = -\frac{40}9(x - 1.5)^2 + 10[/tex]

See attachment for the graph that models the path

Read more about quadratic functions at:

https://brainly.com/question/11441586

Ver imagen MrRoyal