Question

Find the area enclosed by each of the following figures.

Answer 1

$$\begin{array}{cc}& \text{(i) Area}=\text{area of}\square AEDC+\text{area of}△ABC\text{[ref. image (i)}]\\ & =4\times 4+\frac{1}{2}\times 4\times 2\\ & =16+4=20{cm}^2\\ & \text{(ii) Area}=\text{are of trapezium DEFC}+\text{area of}\square ABCF\text{[ref. image (ii)]}\\ & =\frac{8}{2}\times (7+18)+18\times 18\\ & =4\times 25+18\times 18\\ & =100+324\\ & =424{cm}^2\\ & \text{(iii) Area}=\text{area of trapezium EDAF}+\text{area of}\square ABCD[\text{ref. image (iii)]}\\ & =\frac{8}{2}\times (6+20)+20\times 20\\ & =4\times 26+400\\ & =104+400\\ & =504{cm}^2\end{array}$$