Quadrilaterals
Any plane figure with 4 sides is called a quadrilateral. A plane figure is a flat figure (2D shape) All quadrilaterals have 4 angles bounded by 4 straight sides. Straight lines that joins opposite angles are called diagonals. The sum of the angles in a quadrilateral is 360°, as all quadrilaterals can be divided into two triangles.
Quadrilaterals can be regular or irregular:
In this section we will go into an indepth look at quadrilaterals and answer a few question at the end.
Click on the links below to get transferred to whatever information or construction you want to.
Quadrilaterals can be regular or irregular:
 A quadrilateral that can be divided by a diagonal into two equal triangles is a regular quadrilateral.
 If you join the diagonal and the resulting triangles are not equal then it is an irregular quadrilateral.
In this section we will go into an indepth look at quadrilaterals and answer a few question at the end.
Click on the links below to get transferred to whatever information or construction you want to.
Types of a Quadrialterals  In this section we will go through all the different types of quadrilaterals and all the special properties that are associated with each.

Quadrilateral Proofs
There is a couple of things that will never change regardless of what type of quadrilateral you have but it is still important to understand why they are true and understand why they never change. For more information on these proofs click on the link below.
Prove the diagonals of a parallelogram bisect each other  In this section we are going to prove that regardless of the shape of the quadrilateral you are faced with that the angles within it will always add up to 360°

The sum of the interior angles of a Quadrilateral ass up to 360°  In this section we are going to prove that if we joint the diagonals on a parallelogram, that these two lines will bisect each other into equal lengths.

Questions on Quadrilaterals
At this stage we have covered all the basic information we need to construct quadrialterals so if you are confident on all the information covered up until this stage it is time to attempt a few questions. These questions will also incorporate information we learned in all the previous sections of this website. Click on the link below.
