BCDE is a rectangle which has a breadth of 10 m. It is divided into 4 triangles. Triangle F is
113 of the area of the rectangle and
14 the area of Triangle H. Triangle G has an area of 39 m
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
F |
G |
H |
Rectangle |
1 |
|
|
13 |
1 |
|
4 |
|
1 u |
1.5 u |
4 u |
13 u |
(a)
Area of Triangle G
= Half of Rectangle BCDE - Triangle H - Triangle F
= (13 u ÷ 2) - 1 u - 4 u
= 1.5 u
1.5 u = 39
1 u = 39 ÷ 1.5 = 26
Area of the rectangle
= 13 u
= 13 x 26
= 338 m
2 (b)
Length of the rectangle
= 338 ÷ 10
= 33.8 m
Perimeter of the rectangle
= 33.8 x 2 + 10 x 2
= 87.6 m
Answer(s): (a) 338 m
2; (b) 87.6 m