A rocket is launched from a tower. The height of the rocket, y in feet, is related to the
time after launch, x in seconds, by the given equation. Using this equation, find the
maximum height reached by the rocket, to the nearest tenth of a foot.
y = -16x2 + 125x + 147

Respuesta :

Answer:

The maximum height of the rocket is about 391.1 feet.

Step-by-step explanation:

The height of the rocket y in feet x seconds after launch is modeled by the equation:

[tex]y=-16x^2+125x+147[/tex]

We want to find the maximum height reached by the rocket.

Since this is a quadratic equation, the maximum height occurs at the vertex. The vertex of a quadratic is given by:

[tex]\displaystyle \left(-\frac{b}{2a}, f\left(-\frac{b}{2a}\right)\right)[/tex]

In this case, a = -16, b = 125, and c = 147.

Thus, the x-coordinate of our vertex is:

[tex]\displaystyle x=-\frac{125}{2(-16)}=\frac{125}{32}[/tex]

To find the maximum height, we will substitute this value back in. So:

[tex]\displaystyle y_{\text{max}}=-16\left(\frac{125}{35}\right)^2+125\left(\frac{125}{32}\right)+147\approx391.1\text{ feet}[/tex]

The maximum height of the rocket is about 391.1 feet.