|Geometric shapes on the Plane_3|
|1. THE AREA OF A RHOMBUS (1st WAY)|
rhombus is a special kind of parallelogram with four equal sides. If
we know the base and height we can use the formula for working out the
area of a parallelogram. However, the area of a rhombus is often
expressed by referring to its diagonal lines. The
area of a rhombus, in terms of its diagonals is:
In the shape below you can see that we have called the diagonals a and b. We have also drawn a rectangle around the rhombus as we are going to use the rectangle to help us work out the area of a rhombus.
1.- Click on the button and four green triangles should appear which are the same as the four triangles that make up the rhombus.
2.- Therefore we can say that the area of a rhombus is half of the area of a rectangle.
|2. THE AREA OF A RHOMBUS ( 2nd WAY )|
In the following window we can see how a different construction can be used to work out the area of a rhombus.
1.- Follow all the steps indicated by the window and then try to explain how this demonstration works to find out the area.
2.- Go back to the area of a triangle page and review the window where we constructed different triangles with the same area. This will help you to understand step 3.
|Agustín Muñoz Núñez|
|Spanish Ministry of Education. Year 2001|
Except where otherwise noted, this work is licensed under a Creative Common License