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Geometry Difficulty 2.5 Junior Find the answer Canada

In the diagram, $\triangle PQR$ has base $PQ=8~\text{cm}$ and height $6~\text{cm}$ . $\triangle PST$ has base $PS=4~\text{cm}$ and height $3~\text{cm}$ .

What is the area of the shaded region?

Pick one

Solution

The area of $\triangle PQR$ is $\$\dfrac12\times8\text{ cm}\times6\text{ cm}=24\text{}$ cm}^2 $. The area of$ $\triangle$ PST $is$ $\dfrac12\times4\text{ cm}\times3\text{ cm}=6\text{}$ cm}^2$.

The area of the shaded region is equal to the area of $\triangle PQR$ minus the area of $\triangle PST$ , which is $24\text{ cm}^2-6\text{ cm}^2=18\text{ cm}^2$ .

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