Answer:
b.520 units
Explanation:
find the area of the bigger triangle the base is 20 which is 10×2 while the height is 28. 1/2×20×28=280units find the area of the smaller triangle. the base is also 20 while the height is 24. 1/2×20×24=240. sum the areas of the two triangles. 280+240=520units