How to solve 2 (x+y) ^2-9 (x+y) - 5

2 (x + y) ² - 9 (x + y) - 5 = 0

⇒2 (x + y) ² - 10 (x+y) + 1 (x+y) - 5 = 0

⇒2 (x+y) (x + y - 5) + 1 (x + y - 5) = 0

taking (x + y - 5) common,

⇒ (x + y - 5) [2 (x + y) + 1] = 0

⇒ (x + y - 5) (2x + 2y + 1) = 0

hope, you got this