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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.
Sal graphs the following system of equations and solves it by looking for the intersection point: y=7/5x-5 and y=3/5x-1.
Graph a system of equations in slope-intercept or standard form, and find their solution using the graphs.
Sal uses simple elimination to figure out how many cupcakes are eaten by children and adults.
Sal solves another system of equations using elimination.
Sal solves the following system of equations by eliminating x: x-4y=-18 and -x+3y=11.
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
Solve systems of equation with multi-step elimination (e.g., a manipulation is need in order for x-values or y-values to cancel each other out).
Sal solves a systems of equations with substitution.
Sal solves the following system of linear equations using substitution: -3x-4y=-2 and y=2x-5.
Solve systems of equations where one of the equations is solved for one of the variables.
Solve systems of equations with any number of solutions using any solution method.