Jane uses red and blue square tiles to make a design. her design includes 4 squares that are each x tiles long. She has exactly 16 red tiles and uses them all in her design. The number of blue tiles in her design is modeled by the function b(x) = 4x^2 - 16. How can b(x) be written to show how long janes squares are when her design includes zero blue tiles. The possible answers are on the picture.