In the diagram, the area of rectangle EFGH is 1/4 of the area of unit square ABCD. What is the area of quadrilateral AFCH in square units?
Note that quadrilaterals EAHD and BFCG must be 3/4 of the area of the square
But the area of triangle EAH and triangle FCG are 1/2 the area of each of the above quadrilaterals
So.......their combined area must be (1/2) (3/4) = 3/8 units^2
So [ FEGH] +[ EAH ] +[ FCG] = [FACH] = 1/4 + 3/8 = 2/8 + 3/8 = 5/8 units^2