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A detailed tutorial on the definition of a bisector. Step by step tutorial including several examples of bisectors for reference.

A bisector is any line that evenly divides a symmetrical shape or object. The only difference between the bisector and the test for symmetry is that when testing for symmetry, the line is not really there. A bisector is really there. The most common kind of bisector is an angle bisector. In order to remember bisectors, think of them as perpendicular lines that cross right in the middle.

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A detailed tutorial on the definition of a quartile. Step by step tutorial including several examples of the definition of a quartile for reference.

A quartile is a value that separates out statistical data. There are three quartiles, and they work together to separate data out into four different parts. The first quartile, called Q1, is the lower quartile. It is the 25th percentile of data – that is, the median of the median of the total amount of data, and the lowest count in a data set. The second quartile, called Q2, is the median of the entire data set. It is sometimes referred to as the middle value. The third quartile, called Q3, is the upper quartile. It is the 75th percentile of data – that is, the median of the median of the total amount of data, and the highest count in a data set.

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A detailed tutorial on how to make a box-and-whisker plot. Step by step tutorial including several examples of how to make a box-and-whisker plot for reference.

A box-and-whisker plot is named for it’s resemblance to a cat’s face – the box is the face of the cat, and the lines extending out from either side are known as whiskers. Sometimes box-and-whisker plots are simply called box plots. They are used to graph sets of numbers according to five values: the highest value, known as the maximum, the second highest value, known as the upper quartile, the median, or the middle, the second lowest value, known as the lower quartile, and the lowest value, known as the minimum. The box centers around the median and the whiskers extend out to the other numbers.

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A detailed tutorial on symmetry and symmetric images. Step by step tutorial including several examples of symmetry for reference.

Symmetry is a very basic concept in geometry. It is similar to invariance. It is when something is equal to itself through both of its sides. If you compare the two sides of something and they match, then the object is said to be symmetric. When testing an image for symmetry, the easiest test is to draw an imaginary line down the middle. Then pretend to fold the image over. If the two sides are perfect matches of each other, then the image is symmetric.

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A detailed tutorial on locating the origin of a graph. Step by step tutorial including several examples of how to locate the origin for reference.

The origin in mathematical terms means the center. Typically, the term origin is used with a graph in the Cartesian coordinate system. When on a graph, the origin is found at the point (0, 0), where the x-axis and y-axis intersect. Other common things to hear an origin being attributed to are geometrical shapes, most often a circle.