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Transformation Matrices Pages: 1, 2, 3, 4, 5  Vector mathematics
To see how this works, let's review some basic operations on
vectors. The addition of two vectors can be shown graphically.
It works as might be expected: Two vectors [4,3] and [1,2] add
up to [5,5]. Here is how it looks in a graph:  Figure 2  Notice
how the first vector starts from the origin (0,0). The second
vector is then placed with its tail (the end with no arrow head)
to the head of the first. The combination of the two is the same
as a vector starting from the origin connecting to the head of
the second one. Subtraction follows in a similar fashion, but
reverses the direction of the second vector.  Graphing addition
like this, a collection of vectors (each representing a line)
can be used to create basic images, a vector version of connect-
the-dots. Although our example is simple in nature, many vectors
can be combined to generate complex drawings.  Let's try an
example to i