Answer:
(a) This function represents a direct variation because it passes through the origin and has a constant rate of change of $5 per hour.
Step-by-step explanation:
The equation of direct variation is ...
y = kx
for some constant k. Here, we have x in hours and y in dollars. We can see if k is constant for the values given in the table.
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<h3>constant of variation</h3>
Solving the direct variation formula for k, we have ...
k = y/x
Using the table values, we can see if this is constant:
k = dollars/hour = 10/2 = 20/4 = 30/6 = 40/8 = 5
The "rate of change" is constant at $5 per hour.
The function represents direct variation because it passes through the origin and has a constant rate of change of $5 per hour.
