Question

7 + 10 (x + y) - 8 (x + y) ²​

Answer 1

Answer:

7 + 10 (x + y) - 8 (x + y) ²

Let us consider x+y as p.

$= 7 + 10p - 8 {p}^{2} \\ = - 8{p}^{2} + 10p + 7 \\ = - 8{p}^{2} - 4p + 14p + 7 \\ = - 4p(2p + 1) + 7(2p + 1) \\ = (- 4p + 7) (2p + 1)$

2p+1=0 or -4p + 7=0

2p=-1 or 4p=7

p =-1/2 or p= 7/4

x+y = -1/2 or x+y = 7/4