How to Use Diagonals to Identify Quadrilaterals
- 1). Check if any of the lines are parallel. If no pairs of lines are parallel, then you do not have a special quadrilateral. If some pair is parallel, continue to the following steps.
- 2). Find the angle between the two diagonals, using a protractor. If the angle between the lines is 90 degrees, the quadrilateral is either a kite, a square, a rectangle or a rhombus.
- 3). Measure the two diagonals. If they are the same length, the quadrilateral is either a square, a rectangle or a rhombus.