There are several types of quadrilaterals (four sided polygons).
Quadrilaterals have many special properties involving angles and sides.
Refresh your memory here (click on each shape for details):
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These properties can then be used to find missing information about quadrilaterals.
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Example 1
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Example 2
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| ABCD is a rectangle. Find the size of the angles and sides marked by letters. Give reasons. |
ABCD is a parallelogram.
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w + 50 = 90 (angles in a rectangle are 90°) z = 50° (alternate angles on parallel lines) x = 4 cm (opposite sides of rectangle are equal) y = 5 cm (opposite sides of rectangle are equal)
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x = 5.7 cm (opposite sides of a parallelogram) a = 40° (opposite angles of parallelogram) b = 46° (alternate angles on paralllel lines)
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