Answer: 1 hour 20 minutes
Step-by-step explanation:
Given : The old machine could shred a truckload of paper in 4 hours.
Rate of work done by old machine = 
The new machine could shred the same truckload in 2 hours.
Rate of work done by new machine = 
Let 't' be the time taken by both of them working together , then we have the following equation:-
Since 1 hour = 60 minutes
Then, 
Hence, it will take 1 hour 20 minutes to shred the same truckload of paper if Ron runs both shredders at the same time.
Answer:
The answer just so happens to be 6!
The domain is the set of all x values which are defined (appear on the graph) of the function. In this system, all values from negative infinity to 0, but not including zero, and all values above zero, through positive infinity, are valid. We can write this in set builder notation as x: (-∞,0)∪(0,∞).
The range is the set of all y values which are defined in the function. Like the domain, the range of this function contains all value from negative infinity to positive infinity except zero. Same notation: y: : (-∞,0)∪(0,∞).
Yes........its an identity
