Question

if the area.of a rectangle is 84cm square and its length is 12cm find the perimeter of the rectangle​

Answer 1

Answer:

First use the formula of area of rectangle to get the breadth

A= L×B

84=12×B

84÷12=B

7cm =B

Now, you have got the length and breadth of the rectangle .

Now use the formula of perimeter of rectangle to get the perimeter

P=2(L+B)

P=2(12+7)

P=2×19

P=38 cm

Answer 2

Given :-

• Area of a rectangle = 84 cm.

• Length of a rectangle = 12 cm.

To Find :-

• Perimeter of the rectangle.

Solution :-

Let the breadth of the rectangle be x cm.

We know that,

➩  Breadth = Area/Length

➩  x = 84/12

➩  x = 7

Hence, breadth of the rectangle = 7 cm.

Now,

We have to find the perimeter of the rectangle.

Let the perimeter be y.

➩  Perimeter = 2(l + b)

➩  y = 2(l + b)

➩  y = 2(12 + 7)

➩  y = 2 × 19

➩  y = 38.

So,

Perimeter of the rectangle = 38 cm.