Respuesta :

-3(x + 2)² + 18
-3(x + 2)(x + 2) + 18
-3[x(x + 2) + 2(x + 2)] + 18
-3[x(x) + x(2) + 2(x) + 2(2)] + 18
-3(x² + 2x + 2x + 4) + 18
-3(x² + 4x + 4) + 18
-3(x²) - 3(4x) - 3(4) + 18
-3x² - 12x - 12 + 18
-3x² - 12x + 6