Square, Rectangle

Calculating the area for a Square is the simplest, get the overall width and the overall height of the square, multiply the two and the result is the area for the Square.

Triangle

Calculating the area for a Triangle is done by getting the overall width and the overall height of the triangle, multiply the two and divide by half and the result is the area for the Triangle.

Shapes

The area of shape can be determined by simply breaking the shape into sets of square, rectangles or triangles. After you break your shape into squares, rectangles and triangles, find the individual areas and add them to give you the total area of the Shape.