What is the area of the rhombus ABCD below if AC = 6cm, and BE = 4cm?

The diagonal AC of the rhombus ABCD divides it into two triangles of equal areas.

Now, area of Δ ABC = × base × height = × 4 × 6 = 12cm²

Area of the rhombus ABCD = 2 × area of Δ ABC

= 2 × 12 = 24cm²