Adding and subtracting from both sides of an equation : Khan Academy on a Stick

Khan Academy on a Stick

The why of algebra

Why we do the same thing to both sides: Simple equations
Representing a relationship with a simple equation
One-step equation intuition
One step equation intuition introduction
Adding and subtracting from both sides of an equation
Dividing from both sides of an equation
Solving two-step equations
Why we do the same thing to both sides: Multi-step equations
Why we do the same thing to both sides basic systems
Why all the letters in algebra?

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