Question

11. The perimeter of a rectangle is 120 cm. and it length is 40 cm. Find the
area of the rectangle.​

Answer 1

Step-by-step explanation:

perimeter of rectangle = 120cm

length = 40cm

p=2(l+b)

120cm=2(40cm+b)

130cm=80cm+2b

2b = 120-80

b= 40/2=20

area= l*b

area= 40×20

area= 800cn^2

I hope it helps you

Answer 2

SOLUTION:-

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➝ Here, the question has given us the perimeter of a rectangle that is 120 cm and length that is 40 cm respectively. Now, the question has asked us to find the area of the given rectangle. First of all we will find the breadth. We simply have to apply the formula of perimeter of rectangle to find the breadth and for area we need to apply the formula of area of rectangle and we will get our answer.

ANSWER:-

☆ Breadth of the rectangle = 20 cm

☆ Area of the rectangle = 800 cm²

GIVEN:-

↣ Length of the rectangle = 40 cm

↣ Perimeter of the rectangle = 120 cm

FIND:-

➱ Breadth of the rectangle = ?

➱ Area of the rectangle = ?

FORMULAE:-

➮ Perimeter of rectangle = 2(L + B) [To find the breadth]

➮ Area of rectangle = L × B

Where,

• L = Length
• B = Breadth
• A = Area
• P = Perimeter

SOLVING BY APPLYING THE FORMULA:-

• FINDING THE BREADTH:-

☞ Perimeter = 2(L + B) [Finding Breadth]

☞ 120 = 2(40 + B)

☞ Taking 2 to LHS.

☞ 120 / 2 = (40 + B)

☞ 60 = 40 + B

☞ Taking 40 to LHS.

☞ 60 - 40 = B

☞ 20 = B

☞ B = 20 cm

Hence, we got the breadth of the rectangle. Breadth of the rectangle is 20 cm.

• FINDING THE PERIMETER:-

☞ Area = L × B

☞ Area = 40 cm × 20 cm

☞ Area = 40 cm × 20 cm = 800 cm²

☞ Area = 800 cm²

Hence, we got the area of the rectangle. Area of the rectangle is 800 cm².

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