MNPQ is a rectangle which has a breadth of 10 cm. It is divided into 4 triangles. Triangle R is
112 of the area of the rectangle and
13 the area of Triangle T. Triangle S has an area of 26 cm
2.
- Find the area of the rectangle.
- Find the perimeter of the rectangle.
R |
S |
T |
Rectangle |
1 |
|
|
12 |
1 |
|
3 |
|
1 u |
2 u |
3 u |
12 u |
(a)
Area of Triangle S
= Half of Rectangle MNPQ - Triangle T - Triangle R
= (12 u ÷ 2) - 1 u - 3 u
= 2 u
2 u = 26
1 u = 26 ÷ 2 = 13
Area of the rectangle
= 12 u
= 12 x 13
= 156 cm
2 (b)
Length of the rectangle
= 156 ÷ 10
= 15.6 cm
Perimeter of the rectangle
= 15.6 x 2 + 10 x 2
= 51.2 cm
Answer(s): (a) 156 cm
2; (b) 51.2 cm