boundary line	A line that divides the coordinate plane into two regions. If points along the boundary line are included in the solution set, then a solid line is used; if points along the boundary line are not included then a dotted line is used.
consistent system of linear equations	A system of linear equations that has at least one solution.
coordinate plane	A plane formed by the intersection of a horizontal number line called the x-axis and a vertical number line called the y-axis.
dependent linear equations	Equations that graph as the same straight line.
elimination method	A method of solving a system of equations. Given a system, the elimination method allows you to add the two equations in order to eliminate a common variable.
equation	A mathematical statement that two expressions are equal.
inconsistent system of linear equations	A system of linear equations that has no solutions.
independent linear equations	Equations that graph as different straight lines.
substitution method	A method of solving a system of equations. Given a system, the substitution method allows you to create a simpler, one-variable equation by substituting one quantity in for an equivalent quantity.
system of linear equations	Two or more linear equations with the same variables.
system of linear inequalities	Two or more linear inequalities with the same variables.