Answer:
The ball can be knocked down at a horizontal distance of 3.09 feet or 102.17 feet from the marshal.
Step-by-step explanation:
We have the function that represents the height h (x) of the ball [tex]h(x) = -0.0095x^2 + x + 7[/tex]
Where x is the horizontal distance of the ball.
We want to find the horizontal distance the ball is at (horizontal distance between the field marshal and the ball) when it is at a height of 10 feet.
To do this, we must do h (x) = 10
[tex]10 = -0.0095x^2 + x + 7\\0 = -0.0095x^2 + x -3[/tex]
Now we must solve the second degree equation. For this we use the formula of the resolvent:
[tex]\frac{-b + \sqrt{b ^ 2 - 4 * a * c}}{2a}[/tex]
and
[tex]\frac{-b - \sqrt{b ^ 2 - 4 * a * c}}{2a}[/tex]
[tex]\frac{-1 + \sqrt{1 ^ 2 - 4 * (- 0.0095)(-3)}} {2 (-0.0095)} = 3.09[/tex] ft
and
[tex]\frac{-1 - \sqrt{1 ^ 2 - 4 * (- 0.0095)(-3)}} {2 (-0.0095)} = 102.17[/tex]ft
Then, the ball can be knocked down at a horizontal distance of 3.09 feet or 102.17 feet from the marshal.