Question

Find the perimeter of a rectangle whose length is 63cm and diagonal is 65cm?​

Answer 1

Given:-

The length of the diagonal be d=65cm

The length of a rectangle is =63cm

Therefore, l²+b²=d²

=>63²+b²=65²

=>b²=256

=>b=16cm

Nkw, perimeter =2(16+63)

=2×79

=158cm

Answer 2

Answer:

Step-by-step explanation:

given , length (l) = 63cm

diagonal=65cm

after drawing the diagonal in the rectangle, we get 2 right angled triangles.

in that case by using pythagorus theorem ,

let the unknown side be x,

then, (63)^2 + x^2 = (65)^2

because hypotenuse is 65

x^2 = (65)^2 - (63)^2

x^2 = 4225 - 3969

x^2 = 256

x = _/ 256                   (square root)

x = 16

now perimeter of the triangle is 2(l+b)

l=63cm               (given)

b=16cm               (proved)

therefore , 2(63+16)

 2(79)

   158

therefore , the perimeter is 158cm