Question

Find the area of quadrilateral in which A=90degree,AB=40cm,BC=15cm,CA=28cm,DA=9cm.

Answer 1

DC² = 28² – 9²

= 703

 

DC = 26.51

 

Using Heron’s formula

 

Finding area of ADC

 

s = ½(26.51+ 28 + 9) = 31.76

 

Area = √[ 31.76(31.76-26.51)( 31.76-28)( 31.76-9)]

= 119.45

 

 

Finding area of ABC

 

s = ½(28+40+15) = 41.5

 

Area = √[ 41.5(41.5-28)( 41.5-15)( 41.5-40)]

= 149.23

 

Total area = 119.45 + 149.23

 

                   = 268.68 cm²

Answer 2

Thank you for asking this question. Here is your answer:

DC² = 28² – 9²

= 703

= 26.51 (DC)

Now we will find the area of ADC

s = ½(26.51+ 28 + 9) = 31.76

Area = √[ 31.76(31.76-26.51)( 31.76-28)( 31.76-9)]

= 119.45

Now we will find the area of ABC

s = ½(28+40+15) = 41.5

Area = √[ 41.5(41.5-28)( 41.5-15)( 41.5-40)]

= 149.23

So the total area is = 119.45 + 149.23

= 268.68 cm²

If there is any confusion please leave a comment below.