Answer:
its 88mm^2
Explanation:
you have to split the shape into 2.
work out the big square first which would be 8×8=64 cm^2
then work out the smaller rectangle but because it says 12cm is the total length you do 12-8 which is 4 as the previlious shape tells you the length at the top.
now to work out the smaller rectangle you do 4×6= 24cm^2
finally add the areas of both the individual shapes up and that should give you the area 88mm^2 for the entire compound shape