Answer:
The domain represents the time of motion of the meteor as it falls from 100 km height above the Earth's surface at a speed of 20 km
Step-by-step explanation:
The given parameters from the question are;
The elevation of the meteor above the Earth's surface = 100 km
The rate at which the meteor falls = 20 km per second
The 'x' values represent the time in seconds and the 'y' values represent the meteor's height
Therefore, we have;
y = 100 - 20·x
The domain of a function is the set of inputs to the function
Therefore, the domain represent the time it takes the meteor to reach the given 100 km height above the Earth's surface
At the start x = 0 seconds
On the Earth's surface, y = 0, therefore;
0 = 100 - 20·x
x = 100/20 = 5
When the meteor just touches the Earth's surface x = 5 seconds
Therefore, the domain is 0 ≤ x ≤ 5.
