QUADRILATERALS
1. A square is a parallelogram with four equal sides
   and four 90 degree angles.
2. The perimeter of a square is 4 times the length
   of a side.
3. The area of the square is the length of a side squared.
4. The diagonal of a square is a length of a side times
   the square root of 2.
5. The sum of the angles of a quadrilateral (a for sided
   figure) is 360 degrees.
6. A retangle is a parallelogram that has four 90 degree
   angles and two pairs of equal sides.
7. A cube is a three dimensional figure with all sides]
   equal.
8. The volume of a cube is the qube of a side, or the
   length of a side times itself three times.
9. The volume of a retangular solid is its lenght times
   its width times its height.
10. A trapezoid is a quadrilateral that has one pair of
    opposit sides parallel.
11. The area of a trapezoid is (base1 + base2) times the
    height divided by 2 or
    (b1+b2)*h/2.
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