The figure, not drawn to scale, is made up of 2 triangles, AGH and EGH. AB is
12 of EF. CD is
67 of AB and the difference between EF and CD is 24 cm. Given that HG = 18 cm, find the area of the entire figure.
AB |
EF |
CD |
1x7 |
2x7 |
|
7x1 |
|
6x1 |
7 u |
14 u |
6 u |
8 u = 24 cm
1 u = 24 ÷ 8 = 3 cm
Length of AB
= 7 u
= 7 x 3
= 21 cm
Length of EF
= 14 u
= 14 x 3
= 42 cm
Length of CD
= 6 u
= 6 x 3
= 18 cm
Area of Triangle AGH
=
12 x 18 x 21
= 189 cm
2 Area of Triangle EHG
=
12 x 18 x 42
= 378 cm
2 Area of Triangle CHG
=
12 x 18 x 18
= 162 cm
2 Area of the figure
= 189 + 378 - 162
= 405 cm
2 Answer(s): 405 cm
2