There are 3 variables. Amount of Hotdogs, Amount of Hamburgers, Amount of Hamburgers, and the hamburgers are repeated due to it being doubled
so the equation would be 3x=45 we would then get x=15 we apply that to 15 HotDogs 15 Hamburgers and another 15 Hamburgers.
So in total Mr.Thomas cooked 30 Hamburgers and 15 HotDogs