1. Calculating the Area of a Right Triangle
Look at the area of the rectangle: Base x Height = 6 x 3 = 18 sq. units
Think of a triangle as “half of a rectangle”…
The area of a triangle = ½ x (Base x Height) = ½ x 6 x 3 = 9 sq. units
Height = 3
Base = 6

2. Calculating the Area of Any Triangle
1) Make a parallelogram.
2) Change to a rectangle of equal area.
3) Take half of the rectangle to make right triangle.
4) Area is still ½ x Base x Height – ½ x 4 x 2 = 4 sq. units.
<- Height = 2 ->
 Base = 