Question

Area of rectangle whose breadth is 8 cm and length of the diagonal is 17 cm is____ sq. cm.

A] 104
B] 112
C] 120
D] 136​

Answer 1

Step-by-step explanation:

Breadth=8cm

Diagonal=17 cm

In rectangle ABCD

In right angled triangle ∆BCD

We have,

Hypotenuse=17cm

Perpendicular=8cm

Base= ?

By using Pythagoras theorem

BD^2= BC^2 + CD^2

17^2= 8^2 + CD^2

289= 64 + CD^2

289-64 = CD^2

225= CD^2

CD= 15cm

We have length= 15cm

Perimeter of the rectangle= 2(l + b)

                                           = 2(15 + 8)

                                           = 2(23)

                                           = 46cm

Area of the rectangle = l * b

                                    =15*8

                                    = 120sq.cm