The diagonal of a parallelogram divides the figure into two equal triangles. The area of each triangle is equal to one half the area of the parallelogram.
(figure available in print form)
Area of ABCD = AB x h
Area of ABC= 1/2 X AB x h
Area of a triangle = 1/2 x base x altitude
A = 1/2 bh
Find the area of a triangle whose base is 23.9 ft. and whose altitude is 14.8 ft.
A =1/2 bh A-1/2 x 23.9 x 14.8 =1/2 x 353.72 =176.86 sq.ft.