Linear Pair vs. Straight Angle In geometry, a straight angle has a value of 180° or π radians. However, it doesn't appear to be an angle at all because the lines or opposite rays that meet at the ...

A rectangle has two pairs of equal sides. It has four right angles (90°). The opposite sides are parallel. The diagonals bisect each other. A parallelogram has two pairs of equal sides. It has ...

When two lines cross, they form vertically opposite angles. Vertically opposite angles are equal. When a line cuts through a pair of parallel lines it creates pairs of angles with special properties.

Details of the variation in geometry have been analyzed extensively but generally only with respect to variation in the mean grazing angle. Much of this variation is due to the angular variation in ...