21. Please solve

Graph the parabola and give its vertex, axis of symmetry, x-intercepts, and y-intercept. y = 2x + 4x -8 The vertex is (Type an ordered pair.) The axis of symmetry is (Type an equation. Use integers or fractions for any numbers in the equation.) Select the correct choice below and fill in any answer boxes within your choice. A. The x-intercepts are at x - (Type an exact answer, using radicals as needed. Use a comma to separate answers as needed.) O B. There is no x-intercept. The y-intercept is at y = (Type an integer or a decimal.) Graph the parabola y = 2x + 4x - 8. Click to enlarge graph