Illuminations: Diagonals to Quadrilaterals II

Diagonals to Quadrilaterals II


What types of quadrilaterals are formed when various restrictions are placed on the diagonals?

Instructions

 
The Show and Hide buttons allow three different quadrilaterals and their measurements to appear or disappear on the screen, with the following properties:
  • Show/Hide Perpendicular Bisectors: Draws a quadrilateral for which the diagonals bisect one another and meet at a right angle.
  • Show/Hide Perpendicular Bisectors Congruent: Same as above, but the diagonals are also equal in length.
  • Show/Hide Congruent Bisectors: The diagonals have equal length and bisect one another.

Drag any of the red dots to change the shape or size of a figure.

Exploration

 
Click Show Perpendicular Bisectors. Notice that the measurements of the four interior segments are displayed.
  • Given the measurements of the half-diagonals, what can you conclude about the side lengths of the quadrilateral that is formed?
  • Drag any of the red points to change the size and shape of the quadrilateral. Does the relationship between the side lengths change?
  • What types of quadrilaterals can be formed if the diagonals are perpendicular bisectors?

Conduct a similar investigation for Perpendicular Bisectors Congruent and for Congruent Bisectors. What types of quadrilaterals are formed in each of these cases?

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