In square ABCD, f is the midpoint of AD, BF and AC intersect point G, then the area ratio of triangle BGC and quadrilateral CGFD is? How to write the correct procedure?

In square ABCD, f is the midpoint of AD, BF and AC intersect point G, then the area ratio of triangle BGC and quadrilateral CGFD is? How to write the correct procedure?

Let G be Ge ⊥ BC at point E, G be GH ⊥ BC at point h, and ab = 2, then AF = ad = 1 ⊥ s △ ABF = 1 s ⊥ ABC = 2 ⊥ AF ∥ BC ∪ fag = ⊥ BCG ⊥ AGF = ⊥ cgb ≁ AGF ≁ cgb ≁ AF: BC = 1:2 ≁ Ge: GH = 1:2 ≁ CD = eh = 2 ≁ Ge = 2 / 3 ≁ s ≁ BCG = 2 / 3 s CGFD = (1 + 2) × 2 × 1 / 2 =