Найдите корень уравнения; (x + 2)²+ 6x – 18 = (x + 4)(x - 4) + 9x

Expand both sides of the equation:
(x² + 4x + 4) + 6x – 18 = x² - 16 + 9x
Simplify: x² + 10x – 14 = x² + 9x – 16
Subtract x² from both sides: 10x – 14 = 9x – 16
Subtract 9x from both sides: x – 14 = –16
Add 14 to both sides: x = –2