Answer:
38x² - 17x - 3
Explanation:
The area of the shaded region is calculated as
area of outer rectangle - area of white rectangle, that is
(8x + 1)(5x - 3) - 2x(x - 1) ← expand (8x - 1)(5x - 3) using FOIL
= 40x² - 24x + 5x - 3 - 2x² + 2x ← collect like terms
= 40x² - 17x - 3