The figure, not drawn to scale, is made up of 2 triangles, CJK and GJK. CD is
12 of GH. EF is
56 of CD and the difference between GH and EF is 70 cm. Given that KJ = 15 cm, find the area of the entire figure.
CD |
GH |
EF |
1x6 |
2x6 |
|
6x1 |
|
5x1 |
6 u |
12 u |
5 u |
7 u = 70 cm
1 u = 70 ÷ 7 = 10 cm
Length of CD
= 6 u
= 6 x 10
= 60 cm
Length of GH
= 12 u
= 12 x 10
= 120 cm
Length of EF
= 5 u
= 5 x 10
= 50 cm
Area of Triangle CJK
=
12 x 15 x 60
= 450 cm
2 Area of Triangle GKJ
=
12 x 15 x 120
= 900 cm
2 Area of Triangle EKJ
=
12 x 15 x 50
= 375 cm
2 Area of the figure
= 450 + 900 - 375
= 975 cm
2 Answer(s): 975 cm
2