Answer:
81 m^2
Step-by-step explanation:
First find the area of the lower rectangle
A = l*w
A = 12* 5 = 60m^2
Then we find the area of the middle rectangle
The height is 4m - 3m = 1 meter
The length is 12m - 3m = 9m
A = 9*1 = 9m^2
Then we find the area of the top rectangle
The length is 4 m and the width is 3 m
A = 3*4 = 12m^2
The total area is 60+9+12 =81 m^2
