Difference between revisions of "Linear equation"

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Linear equations are any algebraic equations where both sides of the equation are [[polynomials]] or [[monomials]] of the first [[degree]].
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In [[elementary algebra]], '''linear equations''' are algebraic [[equation]]s in which both sides of the equation are [[polynomials]] or [[monomials]] of the first [[degree]] - i.e. each term does not have any variables to a power other than one.  
  
== Single-Variable Equations ==
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== Form and Connection to Analytic Geometry ==
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In general, a linear equation with <math>n</math> variables can be written in the form <math>\displaystyle\sum_{i=1}^{n}a_ib_i=c</math>, where <math>a_i</math> is a series of constants, <math>b_i</math> is a series of variables, and <math>c</math> is a constant.
  
Single-variable linear equations can '''always''' be expressed in the form:
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For the particular case <math>n=1</math>, the resulting equation can be graphed as a point on the number line, and for the case <math>n=2</math> (resulting in a [[linear function]]), it can be graphed as a line on the [[Cartesian plane]], hence the term "linear" equation. This can extended to a general Cartesian n-space, in which the linear equation with the corresponding number of variables can be graphed as an n-1-space - this concept is the idea behind [[analytic geometry]] as envisioned by Fermat and Descartes.
<math>ax+b=0</math>
 
  
where <math>a</math> and <math>b</math> are constants and <math>x</math> is the variable.
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== Systems, solutions and methods of solving ==
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=== Variable Elimination ===
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=== Matrices and Cramer's Law ===
  
From this form, they can be solved with the following steps:
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==See Also==
  
1. subtract <math>b</math> from both sides.
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[[Category:Analytic geometry]]]
 
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[[Category:Definition]]
2. divide <math>a</math> from both sides.
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[[Category:Elementary algebra]]
 
 
== Two-Variable Equations ==
 
 
 
Two-variable linear equations can '''always''' be expressed in the form:
 
<math>y=mx+b</math>
 
 
 
Where <math>y</math> and <math>x</math> are variables and <math>m</math> and <math>b</math> are constants.
 
 
 
Two-variable linear equations can be drawn as a straight line on a coordinate plane.
 
<math>m</math> can be defined as the [[slope]] and <math>b</math> can be defined as the [[y-intercept]]
 

Revision as of 21:15, 4 December 2008

In elementary algebra, linear equations are algebraic equations in which both sides of the equation are polynomials or monomials of the first degree - i.e. each term does not have any variables to a power other than one.

Form and Connection to Analytic Geometry

In general, a linear equation with $n$ variables can be written in the form $\displaystyle\sum_{i=1}^{n}a_ib_i=c$, where $a_i$ is a series of constants, $b_i$ is a series of variables, and $c$ is a constant.

For the particular case $n=1$, the resulting equation can be graphed as a point on the number line, and for the case $n=2$ (resulting in a linear function), it can be graphed as a line on the Cartesian plane, hence the term "linear" equation. This can extended to a general Cartesian n-space, in which the linear equation with the corresponding number of variables can be graphed as an n-1-space - this concept is the idea behind analytic geometry as envisioned by Fermat and Descartes.

Systems, solutions and methods of solving

Variable Elimination

Matrices and Cramer's Law

See Also

]