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Introduction to 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". This tutorial shows you how to solve systems of equations graphically.
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
Using elimination to solve a system of equations
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).
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.