Answer: y = 12.5x
Explanation:
Because 250 bottles are filled every 20 minutes:
250/20=12.5
So, x=1, y=12.5
Hence, x=2 y=25
Because the number of bottles is directly proportional to the operation of the machine so:
12.5=a+b, 25.2a+b
a=12.5, b=0
Therefore, the equation is y = 12.5x
The Desmos graph of y = 12.5x is attached below