2x² + 12x + 11 - (x - 4)²
2x² + 12x + 11 - 1(x - 4)²
2x² + 12x + 11 - 1(x - 4)(x - 4)
2x² + 12x + 11 - 1(x(x - 4) - 4(x - 4))
2x² + 12x + 11 - 1(x(x) - x(4) - 4(x) + 4(4))
2x² + 12x + 11 - 1(x² - 4x - 4x + 16)
2x² + 12x + 11 - 1(x² - 8x + 16)
2x² + 12x + 11 + 1(x²) + 1(8x) - 1(16)
2x² + 12x + 11 + x² + 8x - 16
2x² + x² + 12x + 8x + 11 - 16
3x² + 20x - 5