Write a polynomial that represents the area of the shaded region

(2x – 1) + (x + 3)

(2x – 1)(x + 3)

2((2x – 1) + (x + 3))

(2x – 1) – (x + 3)

The area of a rectangle is given by its length × width. So we get (2x – 1)(x + 3)