Please Help! My quiz is timed!! Which of the following is a linear equation?
A.) y = x
B.) y = x^(2)
C.) y = 5-x^(2)
D.) y = x^(3)+4

Abag contains 5 red marbles , 6 blue marbles and 4 green marbles. susie selects a marble and returns it to the bag before selecting another marble. if susie selects a red marble 6 out of 20 times, what is the experimental probability that the next marble she selects will be a red marble ?