The substitution method can be used when one of the equations in a system has been solved for one of its variables. An example demonstrates.
Solving a system of equations using the substitution method when both equations contain the same variable.
An introduction to using the algebraic method of substitution to solve a system of equations in which one of the equations is not in slope-intercept form.
How to decide whether substitution or elimination is the better method for solving a system of equations when both equations are in the same form and neither has been solved for a variable.
How to decide whether substitution or elimination is the better method for solving a system of equations in which one equation has been solved for a variable.
To avoid working with fractions or other awkward numbers, it is sometimes preferable to eliminate twice instead of eliminating and then substituting.
Presented is a system of equations to which there is no solution the lines are parallel and a system of equations to which the solution is coincident lines the two equations share the same, infinite number of solutions.
When a system of equations gives no clear direction toward either the substitution method or the elimination method, use the one you prefer.