12х + 9 -16х² - 12х + 3х² - 9х + 2х - 6 = 26х - 13х² - 8
12х - 16х² - 12х + 3х² -9х + 2х - 26х + 13х² = -8+6-9
-16х²+3х²-20х²= -11
-33х² = -11
х = -11/-33
х = 1/3
12х + 9 -16х² - 12х + 3х² - 9х + 2х - 6 = 26х - 13х² - 8
12х - 16х² - 12х + 3х² -9х + 2х - 26х + 13х² = -8+6-9
-16х²+3х²-20х²= -11
-33х² = -11
х = -11/-33
х = 1/3