Below are the construction steps to dissect an equilateral
triangle into pieces that can be reassembled into a rectangle.
| Step 1 is to divide the base into four equal
parts and construct the midpoints of the other two sides. |
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| Step 2 is to construct the line segment joining
one of the midpoints to the far quarter point of the base. |
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| Step 3 is to construct perpendiculars from the
'other' midpoint and 'other' quarter point to the segment constructed
in step 2. |
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| The quadrilaterals 1, 2, and 3 and triangle four
shown to the right form the dissection. A way to show that they
can be reassembled into a rectangle starts with a 180 degree
rotation of polygons 2, 3, and 4 about midpoint A. Can you show
whether the rectangle formed is a square? |
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