You can put this solution on YOUR website! let ABCD be your parallelogram
A is bottom left
B is top left
C is top right
D is bottom right.
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let ABCD lean to the right so that point B is slightly to the right of point A.
all you need is a little tilt to show that it's not a rectangle.
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draw diagonals AC and BD.
AC is the long diagonal and BD is the short diagonal.
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BC congruent to AD (opposite sides of a parallelogram are congruent)
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note:
AC and BD are diagonals of the parallelogram.
they are also transversals that intersect two parallel lines (BC and AD).
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angle ACB congruent to angle CAD (opposite internal angles caused by the intersection of a transversal with two parallel lines are congruent).
likewise, angle DBC congruent to angle BDA.
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you have triangles AED congruent to triangle CEB (ASA)
the ASA is formed by:
side BC congruent to side AD
angle ACB congruent to angle CAD
angle DBC congruent to angle BDA.
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CE is congruent to AE (corresponding parts of congruent triangles are congruent)
BE is congruent to DE (same reason).
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a sketch of the parallelogram can be found at this website:
www.geocities.com/gonzo89p
look for 169616 parallelogram
shouldn't be too hard to find.
it's the only one there.
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