Question

Решите уравнение$\sqrt{x+2}$=3x-4

Answer 1

(✓х+2)^2=(3х-4)^2
х+2=9х^2-24х+16
х+2-9х^2+24х-16=0
9х^2-25х+14=0

D=25^2-4×9×14=625-504=121
✓D=11

x1=(25+11)/18
x2=(25-11)/18

x1=2
x2=7/9

Проверка:

✓2+2=3×2-4
✓7/9+2=3×7/9-4

2=2
7/2≠-7/2

Ответ: 2