Systems of equations and inequalities : Khan Academy on a Stick

Khan Academy on a Stick

Algebra II

Trolls, tolls, and systems of equations
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 troll riddle visually
Solving the system of equations visually. Now we can save the prince/princess
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
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 )
How many bags of potato chips do people eat?
Using elimination to solve a system of equations
Systems with elimination practice
Example of solving systems of equations with elimination
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
Inconsistent systems of equations
Systems of equations without a solution
Infinite solutions to systems
Consistent, but dependent systems of equations
Consistent and inconsistent systems
Consistent and Inconsistent Systems
Independent and dependent systems
Independent and Dependent Systems
Practice thinking about number of solutions to systems
Going through a few examples on the Khan Academy practice exercise: http://www.khanacademy.org/math/algebra/systems-of-eq-and-ineq/e/solutions_to_systems_of_equations

Solving systems of equations for the king

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!

Visualizing the solution set for a system of inequalities
Visualizing the solution set for a system of inequalities
Graphing systems of inequalities
Graphing systems of inequalities
Graphing systems of inequalities 2
Graphing systems of inequalities 2

Systems of inequalities

You feel comfortable with systems of equations, but you begin to realize that the world is not always fair. Not everything is equal! In this short tutorial, we will explore systems of inequalities. We'll graph them. We'll think about whether a point satisfies them. We'll even give you as much practice as you need. All for 3 easy installments of... just kidding, it's free (although the knowledge obtained in priceless). A good deal if we say so ourselves!

Systems of three variables
Systems of Three Variables
Systems of three variables 2
Systems of Three Variables 2
Solutions to three variable system
Solutions to Three Variable System
Solutions to three variable system 2
u14 l3 t1 we4 Solutions to Three Variable System
Three equation application problem
Three Equation Application Problem

Systems with three variables

Two equations with two unknowns not challenging enough for you? How about three equations with three unknowns? Visualizing lines in 2-D too easy? Well, now you're going to visualize intersecting planes in 3-D, baby. (Okay, we admit that it is weird for a website to call you "baby.")

Intersecting functions example
Estimating a solution to nonlinear system with calculator
Estimating a solution to nonlinear system with calculator part 2
Non-linear systems of equations 1
Non-Linear Systems of Equations 1
Non-linear systems of equations 2
Non-Linear Systems of Equations 2
Non-linear systems of equations 3
Non-Linear Systems of Equations 3
Systems of nonlinear equations 1
Systems of nonlinear equations 2
Systems of nonlinear equations 3

Non-linear systems of equations

Tired of linear systems? Well, we might just bring a little nonlinearity into your life, honey. (You might want to brush up on your solving quadratics before tackling the non-linear systems.) As always, try to pause the videos and do them before Sal does!