A motorcycle stunt rider jumped across the Snake River. The path of his motorcycle was given approximately by the function H(1) 0.0004.x2 + 2.582 + 700, where H is measured in
feet above the river and is the horizontal distance from his launch ramp.

How high above the river was the launch ramp?

What was the rider's maximum height above the river, and how far was the ramp when he reached maximum height?

Using quadratic function concepts, it is found that:

The height after x seconds is given by the following equation:

Which is a quadratic equation with coefficients

The height of the ramp is the initial height, which is:

Thus, the launch ramp was 700 feet above the river.

The maximum height is the h-value of the vertex, given by:

Then, substituting the coefficients:

The maximum height is of 4866.7 feet.

The horizontal distance is the x-value of the vertex, given by:

The ramp was 3227.5 feet along when he reached maximum height.

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Correct question:

A motorcycle stunt rider jumped across the Snake River. The path of his motorcycle was given

approximately by the function H(t) = - 0.0004.x2 + 2.582 + 700, where H is measured in

feet above the river and is the horizontal distance from his launch ramp.

How high above the river was the launch ramp?

What was the rider's maximum height above the river, and how far was the ramp when he reached maximum height?

A) 700 feet ; 4866.7025 feet above the river

3227.5 Feets from the ramp

Step-by-step explanation:

Given the Height function:

H(t) = 0.0004x^2 + 2.582x + 700

H = height in feet above the river

x = horizontal distance from launch ramp.

How high above the river was the launch ramp?

H(t) = - 0.0004x^2 + 2.582x + 700

To find height of launch ramp above the river, we set the horizontal distance to 0, because at this point, the motorcycle stunt rider is on the launch ramp and thus the value of H when x = 0 should give the height of the launch ramp above the river.

At x = 0

Height (H) =

- 0.0004(0)^2 + 2.582(0)+ 700

0 + 0 + 700 = 700 Feets

B) Maximum height abive the river and how far the rider is from the ramp when maximum height is reached :

Taking the derivative of H with respect to x

dH'/dx = 2*-(0.0004)x^(2-1) + 2.582x^(1-1) + 0

dH'/dx = 2*-(0.0004)x^(1) + 2.582x^(0) + 0

dH'/dx = - 0.0008x + 2.582

Set dH'/dx = 0 and find x:

0 = - 0.0008x + 2.582

-2.582 = - 0.0008x

x = 2.582 / 0.0008

x = 3227.5 feets

To get vertical position at x = 0

Height (H) =

- 0.0004(3227.5)^2 + 2.582(3227.5)+ 700

- 4166.7025 + 8333.405 + 700

= 4866.7025 feet

4866.7025 feet above the river

3227.5 Feets from the ramp