The function y = x2 – 4x + 7 approximates the height, y, of a bird, and its horizontal distance, x, as it flies from one fence post to another. all distances are in feet. complete the square to find and interpret the extreme value (vertex). select two answers: one extreme value and one interpretation. a. minimum at (4, 7) b. when the bird is 4 feet away from the first fence post, it reaches its minimum height of 7 feet. c. when the bird is 2 feet away from the first fence post, it reaches its minimum height of 3 feet. d. minimum at (2, 3)