The first figure, put the triangle on the right in the upper left corner, and it becomes a trapezoid. Upper sole 6, lower sole 12, and height 12. therefore
s =(6+ 12)* 12/2 = 108
In the second graph, the rectangular area-right triangle area is used, and S=5*8- 1/2*3*4=40-6=34.
The third figure is the trapezoid-square area on the right.