Area of trapezoidal = area of triangle ade + triangle cde
let's work with ade . s= sum of all sides / 2 =
( 10.5 + 6.3+ 8.9)/2 = 12.85
using given formula the area of ade =
sqrt ( ( 12.85 )( 12.85 -10.5)( 12.85- 6.3)(12.85 --8.9) )
sqrt ( (12. 85 )( 2.53)( 6.55)( 3.9 5 ) )
sqrt ( 841.12)
29 .00
Area of CDE : s= ( 6.3+ 8.9 + 7.9) /2 = 11.55
area of CDE = sqrt ( ( 11.55 )( 11.55 -6.3)( 11.55 -8.9)( 11.55 -7.9))
= sqrt (11.55 *5.25 *2.65 *3.65 )
sqrt ( 586.5)
24.21
Ans = 29 + 24.21 = 53.21
