area

We  have  three rectangles

One  at  the top  =  13 * 12 = 156 ft^2

One in the middle   = (19 + 12) * 6  =    31 * 6  =  186 ft^2

One at the bottom  =  9 * 6   =  54 ft^2

Total area =   ( 156 + 186 + 54) ft^2 =  396 ft^2 

(9 x 6) + (6 x 31) + (12 x 13)

= 54 + 186 + 156

= 396 ft²

It's just three rectangles..... calculate each and add them together