this took me a while., tricky.. but i got an idea
When you get areas of each figure:
that is:
Red Tri 12
Blue Tri 5
Yellow 7
Green 8
Total 32
When i tried to get area of the big triangle (assuming that it is a perfect triangle), i got 32.5
mmm... now u'r owned... upper figure is not a triangle! it does look like one but, diagonal line of Blue Tri is not linear to the diagonal of the Red Tri., it can't be a triangle, it has so little difference that we cud see it like one