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Solving systems of equations
Whether in the real world or a cliche fantasy one, systems of equations are key to solving super-important issues like "the make-up of change in a troll's pocket" or "how can order the right amount of potato chips for a King's party." Join us as we cover (and practice with examples and exercises) all of the major ways of solving a system: graphically, elimination, and substitution. This tutorial will also help you think about when system might have no solution or an infinite number of solutions. Very, very exciting stuff!
A troll forces us to use algebra to figure out the make-up of his currency. We end up setting up a system of equations
Solving the system of equations visually. Now we can save the prince/princess
Some practice solving systems graphically (exercises available at http://www.khanacademy.org/math/algebra/systems-of-eq-and-ineq/e/graphing_systems_of_equations )
Graph a system of equations in slope-intercept or standard form
Using simple elimination to figure out how many cupcakes are eaten by children and adults
Practice solving systems of equations through simple elimination
Solve systems of equation with one-step elimination (e.g., x-values or y-values cancel each other out).
Using elimination to solve a system of equations
Example of solving systems of equations with elimination
Solving systems of equations with elimination.
Solving systems of equations with substitution.
Solve systems of equations using substitution
Solve systems of equations with substitution and elimination.
Systems of equations without a solution
Consistent, but dependent systems of equations
Consistent and Inconsistent Systems
Independent and Dependent Systems