Question

The perimeter of a classroom is 42. If the length of the classroom is 12 metre, find the breadth of the classroom and hence find the area of the classroom

Answer 1

Answer:

breadth = 9 metre

area of classroom = 108m^2

Step-by-step explanation:

perimeter of rectangle = 2l + 2b

42 = (2*12)+ (2*b)

42 = 24+2b

42-24 = 2b

18 = 2b

18/2 = b

9m = b

area of rectangle = b*l

area of class room

= 9*12

= 108m^2

Answer 2

Step-by-step explanation:

1. Perimeter of a rectangle
2. P=2(lxb)
3. 42=2(12xb)
4. 42=24xb
5. 42=24b
6. b=42÷24}--divide it from 2x21=42,2x12=24
7. b=21÷12}--divide it from 3x7=21,3x4=12
8. b=7 metre

4

1. Area of a rectangle =lxb
2. A=12x7}simplify by 4x1=4,4x3=12

4

3. A=3x7

4. A=21