Verified answer

1) 10 - (7 - 4х - х²) = х² +8х - 9

10 - 7 + 4х + х² = х² + 8х - 9

4х + х² - х² -8х = -9 -10 + 7

-4х = -12

х = 3

Verified answer

Ответ:

10-(7-4х-х²)=х²+8х-9

10-7+4х+х²=х²+8х-9

10-7+9=8х-4х

12=4х

х=3