The perimeter of the rectangle whose length is 60 cm and a diagonal is 61 cm is
a. 120 cm
b. 122 cm
c. 71 cm
d. 142 cm

Solution:

Given, length of the rectangle is 60 cm

Diagonal of the rectangle is 61 cm

We have to find the perimeter of the rectangle.

Consider a rectangle ABCD,

Let AB = 60 cm

AC = 61 cm

Let the breadth of the rectangle be BC.

Considering triangle ABC,

By pythagorean theorem,

AC² = AB² + BC²

61² = 60² + BC²

3721 = 3600 + BC²

BC² = 3721 - 3600

BC² = 121

Taking square root,

BC = 11 cm

Perimeter of rectangle = 2(length + breadth)

= 2(60 + 11)

= 2(71)

= 142 cm

Therefore, the perimeter of the rectangle is 142 cm.

✦ Try This: The perimeter of the rectangle whose length is 20 cm and a diagonal is 11 cm is

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 6

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NCERT Exemplar Class 7 Maths Chapter 6 Problem 16

The perimeter of the rectangle whose length is 60 cm and a diagonal is 61 cm is: a. 120 cm, b. 122 cm, c. 71 cm, d. 142 cm

Summary:

The perimeter of the rectangle whose length is 60 cm and a diagonal is 61 cm is 142 cm

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☛ Related Questions:

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