To find the area of the shaded region, you have to start off with the area of the whole triangle. To find that, you multiply the height and length. length=10 height=8 (10x8=80). Then, since it's a triangle, you have to divide it by two (80/2=40). So, 40 is the area of the whole triangle. Then, you find the area of the white region, which is 12 (3x4=12). Finally, you take the area of the white square and subtract it from the area of the whole triangle (80-12=28). You would get 28.
