Question

Пожалуйста помогите
(c²+2cd+d²)+(5c²-6cd-7d²)

Answer 1

$c {}^{2} + 2cd + d {}^{2} + 5c {}^{2} - 6cd - 7d {}^{2} = 6c {}^{2} - 4cd - 6d {}^{2} = 2(3c {}^{2} - 2cd - 3d {}^{2} )$

Answer 2

$c^{2}+2cd+d^{2} + \\ +5c^{2}-6cd-7{d}^{2} \\ = 6 {c}^{2} - 4cd - 6 {d}^{2}$