Using the given function, it is found that the snowball traveled 4 feet when the height is 20 feet.
<h3>What is the function for the ball's height?</h3>
The height when x feet are traveled is given by:
h(x) = -0.5x² + 6x + 4.
When the height is of 20 meters, we have that h(x) = 20, hence:
20 = -0.5x² + 6x + 4.
0.5x² - 6x + 16 = 0
x² - 12x + 32 = 0
(x - 8)(x - 4) = 0
For the first time: x - 4 = 0 -> x = 4.
The snowball traveled 4 feet when the height is 20 feet.
More can be learned about functions at brainly.com/question/25537936