From the figure, find the area of quadrilateral ABCD when AC = 4 cm.

Area of quadrilateral ABCD = Area of triangle ABC + Area of triangle ADC

Area of a triangle = \(\frac{1}{2}\) ×  Base ×  Height

Area of triangle ABC = \(\frac{1}{2}\) ×  4 × 1.8 = 3.6 cm²

Area of triangle ADC = \(\frac{1}{2}\) ×  4 × 2.2 = 4.4 cm²

Now, Area of quadrilateral ABCD = 3.6 + 4.4

= 8cm²

The correct answer is Option (3) → $8 cm^2$