In the quadratic problem: A train travels 300km at a uniform speed. If the speed had been 5km an hour more, the journey would have taken 2 hours less. Find the speed of the train?
Here the equation is set as 300/x - 300/x+5 = 2
what I would like to know is why I cant set the equation as 300/x+5 - 300/x = 2?
Is there any way to understand this rule?