Students are planting a flower bed for science class. The flower bed can be 4.5 ft wide and will be divided into 2 sections for roses and irises. The iris section will be 3 ft long and it has not yet been determined how long the rose section will be. a) A student in the class claims that the area of the flower bed could be written as 4.5( + 3). Write an equivalent form of this expression. b) How do you know the two expressions are equivalent?