What is the rate of change of y with respect to x of the line represented by y = 9x-4

Geometry? i am really bad at math and have dyscalcullia. .

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup