Search "simultaneous"
Talking bird solves systems with substitution
Solving systems of equations with substitution.
Practice using substitution for systems
Example doing Khan Academy systems of equations exercise at: http://www.khanacademy.org/math/algebra/systems-of-eq-and-ineq/e/systems_of_equations_with_substitution
Solving systems graphically
Some practice solving systems graphically (exercises available at http://www.khanacademy.org/math/algebra/systems-of-eq-and-ineq/e/graphing_systems_of_equations )
King's cupcakes: Solving systems by elimination
Using simple elimination to figure out how many cupcakes are eaten by children and adults
How many bags of potato chips do people eat?
Using elimination to solve a system of equations
Simple elimination practice
Practice solving systems of equations through simple elimination (exercise at http://www.khanacademy.org/math/algebra/systems-of-eq-and-ineq/e/systems_of_equations_with_elimination_0.5 )
Systems with elimination practice
Example of solving systems of equations with elimination
