GHJK is a rectangle which has a breadth of 10 m. It is divided into 4 triangles. Triangle L is
114 of the area of the rectangle and
14 the area of Triangle N. Triangle M has an area of 50 m
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
L |
M |
N |
Rectangle |
1 |
|
|
14 |
1 |
|
4 |
|
1 u |
2 u |
4 u |
14 u |
(a)
Area of Triangle M
= Half of Rectangle GHJK - Triangle N - Triangle L
= (14 u ÷ 2) - 1 u - 4 u
= 2 u
2 u = 50
1 u = 50 ÷ 2 = 25
Area of the rectangle
= 14 u
= 14 x 25
= 350 m
2 (b)
Length of the rectangle
= 350 ÷ 10
= 35 m
Perimeter of the rectangle
= 35 x 2 + 10 x 2
= 90 m
Answer(s): (a) 350 m
2; (b) 90 m