RSTU is a rectangle which has a breadth of 5 cm. It is divided into 4 triangles. Triangle V is
113 of the area of the rectangle and
14 the area of Triangle X. Triangle W has an area of 9 cm
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
V |
W |
X |
Rectangle |
1 |
|
|
13 |
1 |
|
4 |
|
1 u |
1.5 u |
4 u |
13 u |
(a)
Area of Triangle W
= Half of Rectangle RSTU - Triangle X - Triangle V
= (13 u ÷ 2) - 1 u - 4 u
= 1.5 u
1.5 u = 9
1 u = 9 ÷ 1.5 = 6
Area of the rectangle
= 13 u
= 13 x 6
= 78 cm
2 (b)
Length of the rectangle
= 78 ÷ 5
= 15.6 cm
Perimeter of the rectangle
= 15.6 x 2 + 5 x 2
= 41.2 cm
Answer(s): (a) 78 cm
2; (b) 41.2 cm