The length of a rectangular backyard is represented by 4x + 10, and the width is represented by 2x + 5.
An inground swimming pool with an area of 2x² will be installed tomorrow. Write an expression to
represent the remaining area of the backyard.
(1) 8x² + 40x + 50
(3) 2x² + 6x + 15
(2) 6x² + 40x + 50
(4) 6x² + 50