Can the union of two sets have a solution of a null set? Why or why not?

Hell . what are the solutions to `10x^2 - 38x - 8 = 0`? is this when i find the factors and use the numbers within the factors to determine the zeros? i hope that made sense lol

What is the area of the original rectangle? 8 cm² 20 cm² 25 cm² 40 cm²

Which expression is equal to (f+g)(x)?