DEFG is a rectangle which has a breadth of 8 m. It is divided into 4 triangles. Triangle H is
113 of the area of the rectangle and
14 the area of Triangle K. Triangle J has an area of 15 m
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
H |
J |
K |
Rectangle |
1 |
|
|
13 |
1 |
|
4 |
|
1 u |
1.5 u |
4 u |
13 u |
(a)
Area of Triangle J
= Half of Rectangle DEFG - Triangle K - Triangle H
= (13 u ÷ 2) - 1 u - 4 u
= 1.5 u
1.5 u = 15
1 u = 15 ÷ 1.5 = 10
Area of the rectangle
= 13 u
= 13 x 10
= 130 m
2 (b)
Length of the rectangle
= 130 ÷ 8
= 16.25 m
Perimeter of the rectangle
= 16.25 x 2 + 8 x 2
= 48.5 m
Answer(s): (a) 130 m
2; (b) 48.5 m