The vertices of a convex pentagon are (-1, -1), (-3, 4), (1, 9), (8, 5) and (3, -1). What is the area of the pentagon?
Take area of FGIH = (10) (11) = 110
Subtract areas of the right triangles (1/2) [ (4*5 ) + (5*2) + (6*5) + (7*4) ] = 44
Area of pentagon = 110 - 44 = 66
