Question

A rectangle is 8cm long and 5cm wide .It's perimeter is doubled when each of it's sides is increased by x .So the new length of the rectangle is

Answer 1

Answer:

New length =14.5 cm

Step-by-step explanation:

New length =x+8

New breadth=x+5

New perimeter=2×2(L+B)

=4(8+5)

=4×13

=52 cm

New perimeter=New length +New bredth

52=2(x+8+x+5)

52=2(2x+13)

52=4x+26

52-26=4x

26=4x

13/2=x

x=6.5

New length =x+8 =6.5+8=14.5 cm

New breadth = x+5 = 6.5+5=11.5cm

Answer 2

↦Solution : -

Length of rectangle = 8cm

Breadth of rectangle = 4cm

Perimeter of rectangle = ?

Formula : -

Perimeter of rectangle = 2(l + b)

So ,

2(8 + 5)

2(13)

26cm

Given : It's perimeter will be doubled ..

Now ,

26 × 2

52cm

So , the perimeter of the rectangle is 52cm ..

It is given that : -

Each of Perimeter sides is increased by x

So ,

New length of rectangle = 8 + x

New Breadth of rectangle = 5 + x

Perimeter of the rectangle = 52

→2(8 + x + 5 + x) = 52

→2(13 + 2x) = 52

→26 + 4x = 52

→4x = 52 - 26

→4x = 26

→x = 26/4

→x = 6.5 m

So , the value of x is 6.5cm

Now ,

New Length of rectangle = 8 + x

8 + 6.5

14.5cm

New Breadth of rectangle = 5 + x

5 + 6.5

11.5cm

Therefore , New length of the rectangle is 14.5cm and New breadth of the rectangle is 11.5cm ...