Question

the length of rectangle is 5 less than 3 times the breadth. If perimeter is 14. Find length

Answer 1

Answer:

let breadth be=x

length=3x-5

perimeter =22

area of rectangle=3x-5(x)

=3x2-5x

Answer 2

GivEn:

• The length of rectangle is 5 less than 3 times the breadth.
• Perimeter = 14 m

To find:

• Length?

Solution:

• Let's consider ABCD is a rectangle.

Where,

• Length = l = 3b – 5 m
• Perimeter = 14 m

• Let the length and breadth of the rectangle be l and b respectively.

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« Now, Finding breadth first,

★ P = 2(l + b)

➻ 14 = 2(3b - 5 + b)

➻ 3b - 5 + b = 14/2

➻ 3b - 5 + b = 7

➻ 4b = 7 + 5

➻ 4b = 12

➻ b = 3 cm

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« Now, Let's find length,

➻ P = 2(l + b)

Putting the value of breadth in the formula,

➻ 2(l + 3) = 14

➻ 2l + 6 = 14

➻ 2l = 14 - 6

➻ 2l = 8

➻ l = 8/2

➻ l = 4 cm

∴ Hence, Length of the rectangle is 4 cm.

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« Now, Let's verify it,

As we know that,

• ★ P = 2(l + b)

➻ 14 = 2(l + b)

➻ 14 = 2(3 + 4)

➻ 14 = 2(7)

➻ 14 = 14

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★ More to know :

• Area of rectangle = length × breadth
• Diagonal of rectangle = √(length² + breadth²)
• Area of square = side × side
• Perimeter of square = 4 × side
• Diagonal of square = √2 × side