Area of Base Formulas

The base of a shape like a polygon is the bottom of the shape. In order to find the area of the base the formula one uses depends on the shape of the object. Here is a list of the most common base area formulas.

Formulas for finding the Area of Base of Geometric Shapes

Triangle
1⁄2 b*h
b=base
h=height
b=base     h =height
 Rectangle
length * width
 
 Trapezoid1⁄2 h ( b_1+ b_2 )
h = height
b_1=base 1
b_2=base 2
 Squares^2 s =side
 Parallelogrambase * altitude
Pentagon1⁄2  a*p  
a = apothem
P = perimeter
Hexagon
1⁄2  a*p  
a = apothem
P = perimeter
 Heptagon
1⁄2  a*p  
a = apothem
P = perimeter
Octagon

1⁄2  a*p  
a = apothem
P = perimeter