Use a graph paper for this question:
- Plot $P \left(6, 3\right)$ and $Q \left(3, 0\right)$.
- Reflect $P$ in the X-axis to get $P'$. Write the coordinates of $P'$.
- $O$ is the origin. Give the geometrical name of $POP'Q$.
- Find the area of the quadrilateral $POP'Q$.
- Points $P \left(6, 3\right)$ and $Q \left(3, 0\right)$ are plotted.
- $P$ reflected in the X-axis gives $P' \left(6, -3\right)$.
- $POP'Q$ is an arrow.
- $\text{Area of } POP'Q = 2 \times \text{Area } \triangle POQ$
$\text{Area }\triangle POQ = \text{Area } \triangle POX - \text{Area } \triangle POX$
i.e. $\;$ $\text{Area }\triangle POQ = \dfrac{1}{2} \times 6 \times 3 - \dfrac{1}{2} \times 3 \times 3 = 9 - 4.5 = 4.5 \; cm^2$
$\therefore \;$ $\text{Area of } POP'Q = 2 \times 4.5 = 9 \; cm^2$