Year 12 Advanced Mathematics Art of Smart in the diagram below. A large window is constructed in the shape of a rectangle with a semicircle on top, as Term 2 as quickly as possible X 2r The glass forming the semicircle is opaque and the glass forming the rectangle is clear. The height of the rectangle is x metres and the radius of the semicircle is r metres. The perimeter of the entire window is 12 metres. a. Show that x = 6 -~r-r