Basic Geometry
Surface Area Examples
Example 1
This cube has six congruent faces, each with a length and width of 3 cm. Area of one face = 3 x 3 cm = 9 cm^{2} Surface area = 6 sides x 9 cm^{2} = 54 cm^{2} 
Example 2
This trapezoidal prism has six sides, two congruent trapezoids and four rectangles.

Example 3
This cylinder has two circles (each with a radius of 2 cm) and one rectangle (with a length of 5.8 cm and a width the circumference of the circles).

Example 4
This pyramid is made up of four equilateral triangles.  Here we just need to find the area of one triangle and multiply it by four sides: Area of 1 triangle = ½bh = ½(8 x 6.9) = 27.6 cm^{2} Now, multiply that by four sides, and we're done. 110.4 cm^{2} 
Example 5
The diameter of this sphere is 11.9 cm, so the radius is half of that, 5.95 cm. 
Example 6
The area of the circular base is equal to: 