samaraparisaca19 samaraparisaca19 03-12-2020 Mathematics contestada find the vertex of the following quadratic function f (x) = -3x² + 7x + 11 a. (0.857 , 4.384) b. (1.166 , 15.083) c. (-2.45 , 3.18) d. (1 , 12)