a) area = ( 1/2 ) (base) (height) = (1/2) (9) (5) = 22.5 square units
b) area = 1/2 x base x height = 1/2 x 7 x 6 = 21 square units
c) area = 1/2 x base x height = 1/2 x 5 x 5 = 12.5 square units
You calculate the length of the sides by counting the number of squares
