Terry throws a ball into a hoop that is 5 feet off the ground. The path of the ball can be modeled by the equation

y
=

x
2
+
4
x
+
5
, where x represents the horizontal distance traveled by the ball, in feet, and y represents the vertical height of the ball, in feet. Since the ball hoop is located 5 feet off the ground, you can use the equation
y
=
5
to model the position of the hoop. Determine the horizontal distance between Terry and the hoop.(1 point)
Responses

5 feet
5 feet

4 feet
4 feet

2 feet
2 feet

0 feet

1 answer

To determine the horizontal distance between Terry and the hoop, we need to find the points where the path of the ball (given by the equation \( y = -x^2 + 4x + 5 \)) intersects the height of the hoop \( y = 5 \).

We can set the two equations equal to find the values of \( x \):

\[ -x^2 + 4x + 5 = 5 \]

Subtract 5 from both sides:

\[ -x^2 + 4x = 0 \]

Factoring out \( x \):

\[ x(-x + 4) = 0 \]

Setting each factor to zero gives us:

  1. \( x = 0 \)
  2. \( -x + 4 = 0 \) ⇒ \( x = 4 \)

So, the ball is at the height of the hoop at \( x = 0 \) feet and \( x = 4 \) feet.

Terry throws the ball from \( x = 0 \) to the hoop which is at \( x = 4 \). Thus, the horizontal distance between Terry and the hoop is:

\[ 4 - 0 = 4 \text{ feet} \]

Therefore, the answer is 4 feet.