rectangle
Rectangle. A quadrilateral whose four angles are equal, that is, whose 4 angles are equal to .
Any rectangle is a parallelogram.
This follows from angles and adding up .
Since parallelograms have their opposite sides equal, so do rectangles. In the picture, and .
Rectangles are the only parallelograms to be also cyclic (since opposite angles add up .
Notice that every square is also a rectangle, but there are rectangles that are not squares
Rectangles have their two diagonals equal (since triangles and are congruent), A nice result following from this is that the quadrilateral obtained by joining the midpoints of the sides is a rhombus.
Since joins midpoints of sides in triangle , we have . Similarly we have , and and thus the sides of quadrilateral are all equal, in other words, is a rhombus.
Title | rectangle |
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Canonical name | Rectangle |
Date of creation | 2013-03-22 12:02:29 |
Last modified on | 2013-03-22 12:02:29 |
Owner | drini (3) |
Last modified by | drini (3) |
Numerical id | 6 |
Author | drini (3) |
Entry type | Definition |
Classification | msc 51-00 |
Related topic | Quadrilateral |
Related topic | Parallelogram |
Related topic | Rhombus |
Related topic | ParallelogramLaw |
Related topic | Square |