Plzzz help I need before six

Which of the following expressions is equal to 2x^2+8

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?

3x + 4y = 5 x- 3y = -7 solve by substitution