A model rocket is launched from a roof into a large field. The path of the rocket can be modeled by the equation y = –0.04x2+ 8.3x + 4.3, where x is the horizontal distance, in meters, from the starting point on the roof and y is the height, in meters, of the rocket above the ground. How far horizontally from its starting point will the rocket land?

A. 208.02 m
B. 416.03 m
C. 0.52 m
D. 208.19 m

3 answers

To find where the rocket will land, we need to find when y=0 (the rocket will be at ground level). So we substitute y=0 into the equation and solve for x:

0 = -0.04x^2 + 8.3x + 4.3

Multiplying by -25 to simplify:

x^2 - 207.5x - 86 = 0

Using the quadratic formula:

x = (207.5 ± sqrt(207.5^2 - 4(1)(-86))) / 2(1)

x = (207.5 ± sqrt(42906.25)) / 2

The two solutions are x = 208.02 and x = -0.52. We can discard the negative solution because we are looking for distance, not direction. Therefore, the rocket will land 208.02 meters horizontally from its starting point, so the answer is A.
are there any exponents in the model rocket's equation?
Yes, the equation for the path of the rocket involves an exponent: y = -0.04x^2 + 8.3x + 4.3. The term -0.04x^2 represents a quadratic function, where x is the independent variable and x^2 is the exponent.