Question

In the figure below, if DE = 2DC and the area of parallelogram ABCD = 20 square units, find the area of $\Delta DBC$ (in square units).

• A. 10
• B. 4
• C. 5
• D. 6

Answer 1

The correct option is C

5

Area of the parallelogram $ABCD=DE\times EF=20$ square units

$DE=2DC\Rightarrow DC=\frac{DE}{2}$

Area of $\Delta DBC=\frac{1}{2}\times DC\times EF=\frac{1}{2}\times \frac{DE}{2}\times EF=\frac{1}{4}\times DE\times EF=(\frac{1}{4}\times 20)$ square units = 5 square units