unknown9965 unknown9965 10-02-2021 Mathematics contestada An equation and the first step in its solution are shown: Equation: x2 + 8x - 9 = 0 Step 1: x2 + 8x +____ = 9+____What number should be put in the____ to solve the equation by the method of completing the square?A. 16B. 12C. 8D. 4