If you let x=money made during second day, then the money made during the first day is x - 150. To total up the money for both days, use the following equation, simplify, and solve for x. But then you will have to calculate x - 150 to get the amount generated on the first day since x will be the amount generated on the second day.
x + (x - 150) = 575
2x - 150 = 575
2x = 725
x = 362.5
As noted above, 362.5 is the amount generated on the second day. 362.5 - 150 = 212.5, which is the amount that was generated on the first day.
To double-check your work, plug x = 362.5 back into the equation we set up and you get 2 * (362.5) - 150 = 575.
In summary, $212.50 was generated on the first day and $362.50 was generated on the second day.
Does this make sense?