Question

The length of a rectangle is 3 cm more than its breadth. If the perimeter of the

rectangle is 46 cm, find the length and the breadth.

Answer 1

Let us assume the breadth of the rectangle be 'b' cm.

So length of the rectangle will be b+3 cm.

Now

Perimeter =46

`\large \mid\orange {2(l + b) = 46}`

`\large \mid\orange {2(b+3+b)=46}`

`\large\mid \orange {2(2b+3) = 46}`

`\large\mid \orange {4b + 6 = 46}`

`\large \mid \orange{4b = 46 - 6}`

`\large\mid \orange {4b = 40}`

`\large \mid \orange{b = (40)/(4) }`

`\large\mid \orange {b = 10}`

`\large \orange{l=b+3= \:10 + 3 = 13 cm }`

Length = 13cm

Breadth = 10cm

Answer 2

breadth = 10 cm

length = 13 cm

Explanation:

so,

perimeter = 46cm

2(l+b) = 46cm

or, 2(3+b+b) = 46cm ( because l = 3+b)

or, 2(3+2b) = 46cm

or, 6 + 4b = 46cm

or, 4b = 46cm - 6

or, 4b = 40cm

or, b = 40/4 cm

so, b = 10 cm

now,

l = 3cm + b

l = 3 cm + 10cm

= 13cm