Respuesta :
Answer:
Let the breadth be x cm
Length be (x+3) cm
Perimeter of Rectangular Sheet of Paper is 42 cm
Perimeter of Sheet = 2 (Length+ breadth)
42 = 2 ( x + x + 3)
42 = 2(2x+3)
42 = 4x + 6
42 -6 = 4x
36 = 4x
36/4 = x
9 = x
Length = 9+3 = 12 cm
So, the length of Rectangular Sheet of paper is 12 cm.
Question : -
The length of rectangular sheet of paper is 3cm more than its breadth.The sheet of paper has a perimeter of 42cm. what is its length ?
Given : -
- Length = 3 cm more than its breadth
- Perimeter of sheet = 42 cm
To Find : -
We have to find the length of rectangular sheet .
Formula Used : -
[tex] \pink{\boxed{Perimeter \: of \: rectangle = 2(l + b)}}[/tex]
Where ,
- l = length of rectangular sheet.
- b = breadth of rectangle sheet.
Concept : -
The concept of this question goes with perimeter of rectangle by making suitable equation with the help of given length and breadth .
To Assume : -
We are assuming breadth of as x cm and,
Length of given rectangular sheet is 3 cm more than its breadth . So length is x + 3 cm .
Let's Start Solving : -
As given perimeter of rectangular sheet is 42 cm and perimeter formula for rectangle is 2 ( l + b ) . So equating the given perimeter with perimeter formula :
- 2 ( l + b ) = 42
Now ,substituting value of length and breadth in it :
- 2 [ ( x + 3 ) + x ] = 42
Now , transposing 2 to right hand side :
- x + 3 + x = 42/2
By dividing 42 by 2 we get :
- x + 3 + x = 21
Now, adding x with x :
- 2x + 3 = 21
Now , transposing 3 to right hand side :
- 2x = 21 - 3
Now , subtracting 3 from 21 :
- 2x = 18
Now , transposing 2 to right hand side :
- x = 18/2
Now , dividing 18 by 2
- x = 9
[tex] \purple{ \boxed{Therefore, \: breadth \: is \: of \: 9 \: cm }}[/tex]
Now , Length of rectangular sheet is equal to ,
- x + 3
- 9 + 3
- 12
[tex]\red{ \boxed{Therefore, \: length \: is \: of \: 12 \: cm }}[/tex]
Verification :
Verifying our answer by putting values of length and breadth in perimeter and formula and it must be equal to 42 cm as it is given in the question :
- 2 ( l + b ) = 42
- 2 ( 12 + 9 ) = 42
- 2 ( 21 ) = 42
- 42 = 42
- L.H.S = R.H.S
- Hence, Verified .
Therefore, our values for length and breadth are correct .