C. No, this is not a valid inference because she asked only 35 families
46+19+54= 119, so the answer is 119
Here is how you would work it out step by step.
You have to factor the equation you're given. (To check you factorization you can "FOIL" it and make sure it matches the original equation)
Then set the two answers you get from FOILing to zero and you should get your answers.