Question

Find the area of the composite figure.19 mm 25 mm 3 mm 6mm

Answer 1

The figure consists of a rectangle and 2 right triangles, as shown in the diagram below

The areas of a rectangle and a triangle are given by the following formulas

`\begin{gathered} A_{\text{rectangle}}=lw \\ A_{\text{triangle}}=(1)/(2)b\cdot h \end{gathered}`

In our case,

`\begin{gathered} A_{\text{rectangle}}=6\cdot19=114 \\ A_{\text{triangle}}=(1)/(2)(25-19)\cdot(3+3)=(1)/(2)\cdot6\cdot6=(36)/(2)=18 \end{gathered}`

Thus,

`\begin{gathered} A_{\text{figure}}=A_{\text{rectangle}}+2A_{\text{triangle}}=114+36=150 \\ \Rightarrow A_{\text{figure}}=150 \end{gathered}`

The total area is 150mm^2