Mighty Hoax level 4-7 is the level where the Golden Egg #9 is located. Fully Zoom out and reach the egg that is placed on the top of the cliff to the right of the screen. The yellow bird is as usual the right choosing to reach it. On the golden egg level itself, try to penetrate the pig pyramid through the middle.
Below you will find the video that shows both the location (or how to find it) and the starred golden egg level walkthrough itself.
Go Back To Our Angry Birds Golden Eggs Guide