Question

find the perimeter of a rectangle whose length is 60 m and diagonal is 61 m​

Answer 1

Step-by-step explanation:

Given :-

A rectangle whose length is 60 m and diagonal is 61 m

To find :-

Find the perimeter of a rectangle?

Solution :-

Given that

Length of a rectangle (l) = 60 m

Let the breadth of the rectangle be b m

Length of the diagonal (d) = 61 m

We know that

The length of the diagonal of a rectangle (d) = √(l²+b²) units

Now,

On Substituting these values in the above formula then

61 = √(60²+b²)

=> 61² = 60²+b²

=> b² = 61²-60²

=> b² = (61+60)(61-60)

Since, (a+b)(a-b) = a²-b²

=> b² = (121)(1)

=> b² = 121

=> b = ±√121

=> b = ±11 m

Since ,the breadth can't be negative .

Therefore, b = 11 m

The breadth of the rectangle = 11 m

We know that

The perimeter of a rectangle = 2(l+b) units

=> P = 2(60+11) m

=> P = 2(71) m

=> P = 142 m

Perimeter = 142 m

Answer:-

Perimeter of the given rectangle is 142 m

Used formulae:-

→ The length of the diagonal of a rectangle (d)

= √(l²+b²) units

→ The perimeter of a rectangle = 2(l+b) units

• l = length
• b = breadth

→ (a+b)(a-b) = a²-b²

Answer 2

Step-by-step explanation:

given :

• find the perimeter of a rectangle whose length is 60 m and diagonal is 61 m

to find :

• find the perimeter of a rectangle

solution :

• Rectangle ABCD is consist two triangle. Let triangle BCD has two sides equal AD = CD = 60 cm and AC = 61 cm

• In AABC,

• - (AC)² = (AB)² + (BC)²

• (61)² = (60)² + (BC)²

• (BC)2 = 3721 - 3600

• ⇒BC √121

• ⇒BC = 11 cm

• Hence, perimeter of the rectangle ABCD = 25(AB + BC)

• ⇒ 2(60 + 11)

• ⇒

• 2(71)

• 142 cm