Answer:
142 square meters
Explanation:
Big rectangle Area = LxW = 18 x9= 162
White triangle Area A = (ab)/2 legs 5 and 8 ( 18-10= 8 )
= (5x8)/ 2 = 20
Subtract white triangle from green rectangle
162-20 = 142
OR
area left rectangle LxW 10x9 = 90
area right rectangle LxW 4x8 =32
area green triangle ( sides 5 an8 ) (ab)/2 = 20
90+32+20 = 142