FGHJ is a rectangle which has a breadth of 12 m. It is divided into 4 triangles. Triangle K is
113 of the area of the rectangle and
14 the area of Triangle M. Triangle L has an area of 36 m
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
K |
L |
M |
Rectangle |
1 |
|
|
13 |
1 |
|
4 |
|
1 u |
1.5 u |
4 u |
13 u |
(a)
Area of Triangle L
= Half of Rectangle FGHJ - Triangle M - Triangle K
= (13 u ÷ 2) - 1 u - 4 u
= 1.5 u
1.5 u = 36
1 u = 36 ÷ 1.5 = 24
Area of the rectangle
= 13 u
= 13 x 24
= 312 m
2 (b)
Length of the rectangle
= 312 ÷ 12
= 26 m
Perimeter of the rectangle
= 26 x 2 + 12 x 2
= 76 m
Answer(s): (a) 312 m
2; (b) 76 m