Question

find the perimeter of the rectangle whose length is 40cm and a diagonal is 41cm answer is. ( hyp ) = ( sum of legs small 2 ). ( 41 small 2 ) = ( 40 small 2 upside ) + ( x ) small upside 2 ( x ) all upside 2 = ( 41 small upside 2 ).- ( 40 ) small upside 2. ( x ) small upside 2 = 1681 - 1600. x = √81 x = 9cm perimeter = 2 × ( l × b ). p small rectangle = 2 × 49 cm. p small rectangle = 98 cm​

Answer 1

Answer:

PR = 41cm

PQ = 40 cm

Let breadth (QR) be x cm

Now, in right angled triangle PQR

\left(PR\right)^2\ =\ \left(RQ\right)^2\ +\ \left(PQ\right)^2(PR)

2

= (RQ)

2

+ (PQ)

2

\left(41\right)^2\ =\ x^2\ +\ \left(40\right)^2(41)

2

= x

2

+ (40)

2

1681\ =\ x^2\ +16001681 = x

2

+1600

1681-\ 1600\ =\ x^21681− 1600 = x

2

\sqrt{81\ }=\ x\

81

= x

9 = x

Therefore of the rectangle = 9 cm

perimeter of the rectange = 2(l+b)

= 2(40+9)

= 2(49)

= 98cm.