blachaze7968 blachaze7968 27-12-2023 Mathematics contestada Convert y = 7x² - 56x - 21 to vertex form by completing the square. Choose the correct equation. 1) y = 7(x - 4)² - 133 2) y = 7(x + 4)² - 133 3) y = 7(x - 4)² + 133 4) y = 7(x + 4)² + 133