Verified answer

Ответ:

[tex]x = \frac{12}{13} [/tex]

Объяснение:

12 - (3x^2 + 5x) + (-8x + 3x^2) = 0

12 - 3x^2 - 5x - 8x + 3x^2 = 0

12 - 5x - 8x = 0

12 - 13x = 0

-13x = -12

[tex]x = \frac{12}{13} [/tex]