155601

a=16T
b=24T
c=24T
d=4T
e=16T
f=18T
g=8T
h=12T

base x slanted height =2x4=8(shape a)
a=16T

8 is half of 16:
bx slanted height=2T
a=1/2t

16 x 0.5 = 8:
T=0.5

Trapeziums:
For trapeziums I found that the same formula doesn't work.

If the length of the top side (of the trapezium)= slanted height, their lengths add up to the length of the base. Therefore b=2h(slant height)

If slant height=1, each time the length of the top side(shorter horizontal line) increases by one, the difference between the area measured by T, and the area found by b x slant height increases by 1 everytime.