(2x+y)^2- (y-2x)^2
pleaseee help me

Which expression is equivalent to (9x - 3 1/ + 1 3/8)

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.

How is this equation completed? i cannot find any examples in the book.