Question

The length of a rectangle is 5 cm more than its breadth. If the perimeter of the rectangle is 50 cm, then what is the area? (a) 150 cm² (b) 250 cm² (c) 900 cm²(d) 800 cm²​

Answer 1

Answer:

the breadth of the rectangle be xcm

Then it's length=x+5cm

Perimeter=2(length+breadth)

⇒70=2(x+(x+5))

⇒

2

70

=2x+5

⇒2x+5=35

⇒2x=35−5=30

⇒x=

2

30

=15cm

Breadth=x=15cm and length=x+5=15+5=20cm

Answer 2

Answer:

(a) 150cm²

Explanation:

Given that,

Length of a rectangle is 5cm more than its breadth.

Then,

If we assume the breadth as ‘x’ cm

Length will be (x + 5) cm

We know,

Perimeter of a rectangle = 2(l + b)

Where, l denotes the length and b is the breadth.

Then, perimeter is

→ 2[(x + 5) + (x)]

→ 2[x + 5 + x]

→ 2[2x + 5]

→ 4x + 10

But, the perimeter is 50cm (given)

So,

→ 4x + 10 = 50

→ 4x = 50 - 10

→ 4x = 40

→ x = 10

Hence, the dimensions are :-

• Breadth = x = 10cm
• Length = (x + 5) = 15cm.

Area of the rectangle is :-

→ l × b

→ 10 × 15

→ 150cm²