Explanation:
System of linear equations
In mathematics, a system of linear equations (or linear system) is a collection of linear equations involving the same set of variables. For example,
is a system of
three equations in the three variables x, y, z. A solution to a linear system is an
assignment of numbers to the variables such that all the equations are
simultaneously satisfied. A solution to the system above is given by
since it makes all three
equations valid.
General
form
A general system of m linear equations with n unknowns can be written as
Here are
the unknowns, are the coefficients of the system,
and are
the constant terms.
Matrix equation
The vector equation is equivalent to a matrix equation of the form
where A is an m×n matrix, X is a column
vector with n entries, and b is a column vector with m entries.
The number of vectors in a basis for the span is now expressed
as the rank of the matrix.
(Our solved example in mathguru.com uses
this concept)
http://en.wikipedia.org/wiki/System_of_linear_equations#Other_methods
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above explanation is copied from Wikipedia, the free encyclopedia and is
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License.