That would be 37.5 percent
A). The area of the shaded triangle is 64cm. This is because the formula for the area of a triangle is (b x h) / 2, and the base of this triangle is 16, and the height is 8. So, 16 x 8 is 128, and 128 / 2 = 64. The area is 64cm.
B). The area of each white triangle is 32cm because we can see that the two white triangles is equal to half of the shaded triangle, so we can take the base of the shaded triangle and divide it in two. Then we can use the formula for the area of a triangle and solve for the area: (b x h) / 2 = (8 x 8) / 2 = 32. The area of one of the white triangles is 32cm.
C). Since we have solved for the area of each of the triangles, we can add up all of these individual areas to get the area for the rectangle: White triangle + white triangle + shaded triangle = 32 + 32 + 64, which is equal to 128cm, the area of the rectangle.
This follows from the half-angle identity for cosine.
