BCDE is a rectangle which has a breadth of 11 cm. It is divided into 4 triangles. Triangle F is
114 of the area of the rectangle and
14 the area of Triangle H. Triangle G has an area of 44 cm
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
F |
G |
H |
Rectangle |
1 |
|
|
14 |
1 |
|
4 |
|
1 u |
2 u |
4 u |
14 u |
(a)
Area of Triangle G
= Half of Rectangle BCDE - Triangle H - Triangle F
= (14 u ÷ 2) - 1 u - 4 u
= 2 u
2 u = 44
1 u = 44 ÷ 2 = 22
Area of the rectangle
= 14 u
= 14 x 22
= 308 cm
2 (b)
Length of the rectangle
= 308 ÷ 11
= 28 cm
Perimeter of the rectangle
= 28 x 2 + 11 x 2
= 78 cm
Answer(s): (a) 308 cm
2; (b) 78 cm