Identify the axis of symmetry and vertex of f(x) = –x^2 –2x–1.   Axis of symmetry: x = 1; Vertex: (– 1, –1) Axis of symmetry: x = – 1; Vertex: (– 1, 0) Axis of symmetry: x = 1; Vertex: (1, 0) Axis of symmetry: x = – 1; Vertex: ( 1, 0) Solve the equation by factoring. C^2-4c=0